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377 commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Sergei Golubchik
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a9035be5b7 | 10.0-base merge | ||
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Sergei Golubchik
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3ad01d00f2 |
error messages: name the storage engine explicitly,
instead of "used storage engine" and similar changes. |
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Sergei Golubchik
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474fe6d9d9 |
fixes for test failures
and small collateral changes mysql-test/lib/My/Test.pm: somehow with "print" we get truncated writes sometimes mysql-test/suite/perfschema/r/digest_table_full.result: md5 hashes of statement digests differ, because yacc token codes are different in mariadb mysql-test/suite/perfschema/r/dml_handler.result: host table is not ported over yet mysql-test/suite/perfschema/r/information_schema.result: host table is not ported over yet mysql-test/suite/perfschema/r/nesting.result: this differs, because we don't rewrite general log queries, and multi-statement packets are logged as a one entry. this result file is identical to what mysql-5.6.5 produces with the --log-raw option. mysql-test/suite/perfschema/r/relaylog.result: MariaDB modifies the binlog index file directly, while MySQL 5.6 has a feature "crash-safe binlog index" and modifies a special "crash-safe" shadow copy of the index file and then moves it over. That's why this test shows "NONE" index file writes in MySQL and "MANY" in MariaDB. mysql-test/suite/perfschema/r/server_init.result: MariaDB initializes the "manager" resources from the "manager" thread, and starts this thread only when --flush-time is not 0. MySQL 5.6 initializes "manager" resources unconditionally on server startup. mysql-test/suite/perfschema/r/stage_mdl_global.result: this differs, because MariaDB disables query cache when query_cache_size=0. MySQL does not do that, and this causes useless mutex locks and waits. mysql-test/suite/perfschema/r/statement_digest.result: md5 hashes of statement digests differ, because yacc token codes are different in mariadb mysql-test/suite/perfschema/r/statement_digest_consumers.result: md5 hashes of statement digests differ, because yacc token codes are different in mariadb mysql-test/suite/perfschema/r/statement_digest_long_query.result: md5 hashes of statement digests differ, because yacc token codes are different in mariadb mysql-test/suite/rpl/r/rpl_mixed_drop_create_temp_table.result: will be updated to match 5.6 when alfranio.correia@oracle.com-20110512172919-c1b5kmum4h52g0ni and anders.song@greatopensource.com-20110105052107-zoab0bsf5a6xxk2y are merged mysql-test/suite/rpl/r/rpl_non_direct_mixed_mixing_engines.result: will be updated to match 5.6 when anders.song@greatopensource.com-20110105052107-zoab0bsf5a6xxk2y is merged |
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unknown
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ddd3e261b2 |
MDEV-254: Server hang with FLUSH TABLES WITH READ LOCK AND DISABLE CHECKPOINT
The code to re-enable checkpointing after UNLOCK TABLES was lost in the 5.5 merge, so re-add it back in. |
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Michael Widenius
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a579adea66 |
Cleanups:
- Don't use SAFEMALLOC on valgrind builds (slows things down) - Added back lost option from 5.3: debug-mutex-deadlock-detector - Flush pages before taking lock mutex (speeds up closing of Aria tables). BUILD/SETUP.sh: - Don't use SAFEMALLOC on valgrind builds (slows things down) sql/lock.cc: Make default argument explicit (improves readability) sql/mysqld.cc: Removed compiler warnings Sorted debug options alphabetically Added back lost option from 5.3: debug-mutex-deadlock-detector storage/maria/ma_close.c: Flush pages before taking lock mutex (speeds up closing of Aria tables). storage/maria/ma_open.c: More DBUG_PRINT storage/maria/maria_def.h: Better DBUG_PRINT storage/maria/trnman.c: Better DBUG_PRINT |
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Sergei Golubchik
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4f435bddfd | 5.3 merge | ||
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Michael Widenius
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24e452a208 | Merge with 5.1 & fixes to IGNORE handling | ||
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Michael Widenius
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6d4224a31c |
Merge with 5.2.
no_error handling for select (used by INSERT ... SELECT) still needs to be fixed, but I will do that in a separate commit |
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Sergey Petrunya
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8e25dcfcd7 |
BUG#868908: Crash in check_simple_equality() with semijoin + materialization + prepared statement
- Part 1 of the fix: for semi-join merged subqueries, calling child_join->optimize() until we're done with all PS-lifetime optimizations in the parent. |
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unknown
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5e7b949e61 | Fix crash due to wrong my_error() call (5.5 after-merge fix). | ||
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Michael Widenius
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6920457142 | Merge with MariaDB 5.1 | ||
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Michael Widenius
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a8d03ab235 |
Initail merge with MySQL 5.1 (XtraDB still needs to be merged)
Fixed up copyright messages. |
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Sergei Golubchik
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0e007344ea | mysql-5.5.18 merge | ||
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Sergei Golubchik
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76f0b94bb0 |
merge with 5.3
sql/sql_insert.cc: CREATE ... IF NOT EXISTS may do nothing, but it is still not a failure. don't forget to my_ok it. ****** CREATE ... IF NOT EXISTS may do nothing, but it is still not a failure. don't forget to my_ok it. sql/sql_table.cc: small cleanup ****** small cleanup |
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Sergei Golubchik
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9809f05199 | 5.5-merge | ||
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Kent Boortz
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68f00a5686 | Updated/added copyright headers | ||
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Kent Boortz
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44135d4725 | Updated/added copyright headers | ||
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Kent Boortz
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02e07e3b51 | Updated/added copyright headers | ||
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Michael Widenius
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6da8ac5f71 |
Added option "AND DISABLE CHECKPOINT" to "FLUSH TABLES WITH READ LOCK"
This makes it possible to do safe multi volume snapshots as long as one snapshots the volume with the transaction logs last. include/mysql_com.h: Added REFRESH_CHECKPOINT mysql-test/r/flush.result: Added test of new FLUSH TABLES syntax + calls to checkpoint_status handler calls mysql-test/t/flush.test: Added test of new FLUSH TABLES syntax + calls to checkpoint_status handler calls sql/handler.cc: Added code to call checkpoint_state for all handlertons that supports it sql/handler.h: Added new checkpoint_state() handlerton call to temporarly disable checkpoints. sql/lex.h: Added CHECKPOINT keyword sql/sql_yacc.yy: Added support for FLUSH TABLES WITH READ LOCK AND DISABLE CHECKPOINT storage/maria/ha_maria.cc: Added handlerton call to disable checkpoints. storage/maria/ma_checkpoint.c: Don't do checkpoint if checkpoints are disabled. storage/maria/ma_static.c: Added maria_checkpoint_disabled storage/maria/maria_def.h: Added maria_checkpoint_disabled storage/xtradb/handler/ha_innodb.cc: Added handlerton call to disable checkpoints. storage/xtradb/include/log0log.h: Added option to log_checkpoint() to allow one to ignore not critical checkpoints during the time checkpoints are disabled. storage/xtradb/log/log0log.c: Added code to allow one to disable checkpoints during a FLUSH TABLES ... DISABLE CHECKPOINT This was done by adding a new argument to log_checkpoint() which tells us when the checkpoint is called by srv_master_thread (which are safe to ignore) storage/xtradb/srv/srv0srv.c: Tell log_checkpoint() that checkpoints from srv_master_thread() are safe to ignore (will just delay recovery time a bit). |
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Sergei Golubchik
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0accbd0364 | lots of post-merge changes | ||
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Michael Widenius
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139a2b64bf | Merge with 5.2 | ||
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Michael Widenius
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3358cdd504 | Merge with 5.1 to get in changes from MySQL 5.1.55 | ||
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Michael Widenius
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869f5d0e81 | Merge with alias as String | ||
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Michael Widenius
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ff3da0f963 |
Change TABLE->alias to String for less memory reallocation
Changed some String.ptr() -> String.c_ptr() for String that are not guaranteed to end with \0 Removed some c_ptr() usage from parameters to functions that takes ptr & length Use preallocate buffers to avoid calling malloc() for most operations. sql/event_db_repository.cc: alias is now a String sql/event_scheduler.cc: c_ptr -> c_ptr_safe() to avoid warnings from valgrind. sql/events.cc: c_ptr -> c_ptr_safe() to avoid warnings from valgrind. c_ptr -> ptr() as function takes ptr & length sql/field.cc: alias is now a String sql/field.h: alias is now a String sql/ha_partition.cc: alias is now a String sql/handler.cc: alias is now a String ptr() -> c_ptr() as string is not guaranteed to be \0 terminated sql/item.cc: Store error parameter in separarte buffer to ensure correct error message sql/item_func.cc: ptr() -> c_ptr_safe() as string is not guaranteed to be \0 terminated sql/item_sum.h: Use my_strtod() instead of my_atof() to not have to make string \0 terminated sql/lock.cc: alias is now a String sql/log.cc: c_ptr() -> ptr() as function takes ptr & length sql/log_event.cc: c_ptr_quick() -> ptr() as we only want to get the pointer to String buffer sql/opt_range.cc: ptr() -> c_ptr() as string is not guaranteed to be \0 terminated sql/opt_table_elimination.cc: alias is now a String sql/set_var.cc: ptr() -> c_ptr() as string is not guaranteed to be \0 terminated c_ptr() -> c_ptr_safe() to avoid warnings from valgrind. c_ptr() -> ptr() as function takes ptr & length Simplify some code. sql/sp.cc: c_ptr() -> ptr() as function takes ptr & length sql/sp_rcontext.cc: alias is now a String sql/sql_base.cc: alias is now a String. Here we win a realloc() for most alias usage. sql/sql_class.cc: Use size descriptor for printf() to avoid accessing bytes outside of buffer sql/sql_insert.cc: Change allocation of TABLE as it's now contains a String _ptr() -> ptr() as function takes ptr & length sql/sql_load.cc: Use preallocate buffers to avoid calling malloc() for most operations. sql/sql_parse.cc: Use c_ptr_safe() to ensure string is \0 terminated. sql/sql_plugin.cc: c_ptr_quick() -> ptr() as function takes ptr & length sql/sql_select.cc: alias is now a String sql/sql_show.cc: alias is now a String sql/sql_string.h: Added move() function to change who owns the string (owner does the free) sql/sql_table.cc: alias is now a String c_ptr() -> c_ptr_safe() to avoid warnings from valgrind. sql/sql_test.cc: c_ptr() -> c_ptr_safe() to avoid warnings from valgrind. alias is now a String sql/sql_trigger.cc: c_ptr() -> c_ptr_safe() to avoid warnings from valgrind. Use field->init() to setup pointers to alias. sql/sql_update.cc: alias is now a String sql/sql_view.cc: ptr() -> c_ptr_safe() as string is not guaranteed to be \0 terminated sql/sql_yacc.yy: r() -> c_ptr() as string is not guaranteed to be \0 terminated sql/table.cc: alias is now a String sql/table.h: alias is now a String storage/federatedx/ha_federatedx.cc: Remove extra 1 byte alloc that is automaticly done by strmake() Ensure that error message ends with \0 storage/maria/ha_maria.cc: alias is now a String storage/myisam/ha_myisam.cc: alias is now a String |
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Michael Widenius
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69fe020f01 |
Fixed bugs found by buildbot:
- Use -Wno-uninitialized if -DFORCE_INIT_OF_VARS is not used, to avoid warnings about not initialized variables. - Fixed compiler warnings - Added a name for each thr_lock to get better error messages (This is needed to find out why 'archive.test' sometimes fails) BUILD/SETUP.sh: Use -Wno-uninitialized if -DFORCE_INIT_OF_VARS is not used, to avoid warnings about not initialized variables. BUILD/build_mccge.sh: Use -Wno-uninitialized if -DFORCE_INIT_OF_VARS is not used, to avoid warnings about not initialized variables. client/mysqltest.cc: Fixed bug in remove_files_wildcards (the orignal code never removed anything) extra/libevent/devpoll.c: Fixed compiler warning include/thr_lock.h: Added a name for each thr_lock to get better error messages. mysql-test/suite/maria/t/maria3.test: Speed up test. mysys/thr_lock.c: Added a name for each thr_lock to get better error messages. Added a second 'check_locks' to find if something goes wrong in 'wake_up_waiters'. sql/lock.cc: Added a name for each thr_lock to get better error messages. storage/xtradb/fil/fil0fil.c: Fixed compiler warning |
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Michael Widenius
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050c004f5e |
Merge with 5.1
Fixes to get Aria handler tests to work. Fixes LP#697597 "HANDLER + Aria asserts in maria-5.3-handler" |
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Michael Widenius
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e63b5546c5 |
Implementation of MWL#172: Add support for prepared statements to HANDLER READ
It includes speed optimizations for HANDLER READ by caching as much as possible in HANDLER OPEN Other things: - Added mysqld option --disable-thr-alarm to be able to benchmark things without thr_alarm - Changed 'Locked' state to 'System lock' and 'Table lock' (these where used in the code but never shown to end user) - Better error message if mysql_install_db.sh fails - Moved handler function prototypes to sql_handler.h - Remove not anymore used 'thd->locked' member include/thr_alarm.h: Added my_disable_thr_alarm include/thr_lock.h: Add new member to THR_LOCK_DATA to remember original lock type state. This is needed as thr_unlock() resets type to TL_UNLOCK. mysql-test/include/check_no_concurrent_insert.inc: Locked -> Table lock mysql-test/include/handler.inc: Locked -> Table lock mysql-test/r/handler_innodb.result: Updated results for new tests mysql-test/r/handler_myisam.result: Updated results for new tests mysql-test/r/sp-threads.result: Locked -> Table lock mysql-test/suite/binlog/t/binlog_stm_row.test: Locked -> Table lock mysql-test/suite/funcs_1/datadict/processlist_val.inc: Locked -> Table lock mysql-test/suite/pbxt/t/lock_multi.test: Locked -> Table lock mysql-test/suite/sys_vars/r/concurrent_insert_func.result: Locked -> Table lock mysql-test/suite/sys_vars/t/concurrent_insert_func.test: Locked -> Table lock mysql-test/suite/sys_vars/t/delayed_insert_limit_func.test: Locked -> Table lock mysql-test/suite/sys_vars/t/query_cache_wlock_invalidate_func.test: Locked -> Table lock mysql-test/suite/sys_vars/t/sql_low_priority_updates_func.test: Locked -> Table lock mysql-test/t/insert_notembedded.test: Locked -> Table lock mysql-test/t/lock_multi.test: Locked -> Table lock mysql-test/t/merge-big.test: Locked -> Table lock mysql-test/t/multi_update.test: Locked -> Table lock mysql-test/t/query_cache_28249.test: Locked -> Table lock mysql-test/t/sp_notembedded.test: Locked -> Table lock mysql-test/t/sp_sync.test: Locked -> Table lock mysql-test/t/status.test: Locked -> Table lock mysql-test/t/trigger_notembedded.test: Locked -> Table lock mysys/thr_alarm.c: Added option to disable thr_alarm mysys/thr_lock.c: Detect loops scripts/mysql_install_db.sh: Give better error message if something goes wrong sql/Makefile.am: Added sql_handler.h sql/lock.cc: Split functions to allow one to cache value if store_lock() (for HANDLER functions). - Split mysql_lock_tables() into two functions, where first one allocates MYSQL_LOCK and other other one uses it. - Made get_lock_data() an external function. - Added argument to mysql_unlock_tables() to not free sql_lock. - Added argument to reset_lock_data() to reset lock structure to initial state (as after get_lock_data()) sql/mysql_priv.h: Moved handler function prototypes to sql_handler.h Added new lock functions. sql/mysqld.cc: Added --thread-alarm startup option sql/net_serv.cc: Don't call vio_blocking() if not needed sql/sql_base.cc: include sql_handler.h sql/sql_class.cc: include sql_handler.h Remove not anymore used 'thd->locked' member sql/sql_class.h: Remove not anymore used 'thd->locked' member sql/sql_db.cc: include sql_handler.h sql/sql_delete.cc: include sql_handler.h sql/sql_handler.cc: Rewrote all code to use SQL_HANDLER instead of TABLE_LIST (original interface) Rewrote mysql_ha_open() to cache all things from TABLE_LIST and items for field list, where etc. In mysql_ha_open() also cache MYSQL_LOCK structure from get_lock_data(). Split functions into smaller sub functions (needed to be able to implement mysql_ha_read_prepare()) Added mysql_ha_read_prepare() to allow one to prepare HANDLER READ. sql/sql_handler.h: Interface to sql_handler.cc sql/sql_parse.cc: include sql_handler.h sql/sql_prepare.cc: Added mysql_test_handler_read(), prepare for HANDLER READ sql/sql_rename.cc: include sql_handler.h sql/sql_show.cc: Removed usage of thd->locked sql/sql_table.cc: include sql_handler.h sql/sql_trigger.cc: include sql_handler.h |
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Michael Widenius
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b7b25dc666 |
Merge with 5.1-release.
- Fixed problem with oqgraph and 'make dist' Note that after this merge we have a problem show in join_outer where we examine too many rows in one specific case (related to BUG#57024). This will be fixed when mwl#128 is merged into 5.3. |
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Sergei Golubchik
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65ca700def |
merge.
checkpoint. does not compile. |
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Michael Widenius
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1a6373e8e2 |
Merge with MySQL 5.1.53
Open issues: - A better fix for #57688; Igor is working on this - Test failure in index_merge_innodb.test ; Igor promised to look at this - Some Innodb tests fails (need to merge with latest xtradb) ; Kristian promised to look at this. - Failing tests: innodb_plugin.innodb_bug56143 innodb_plugin.innodb_bug56632 innodb_plugin.innodb_bug56680 innodb_plugin.innodb_bug57255 - Werror is disabled; Should be enabled after merge with xtradb. |
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Michael Widenius
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52090a4434 |
Code cleanup to get fewer reallocs() during execution.
- Changed TABLE->alias to String to get fewer reallocs when alias are used. - Preallocate some buffers Changed some String->c_ptr() -> String->ptr() when \0 is not needed. Fixed wrong usage of String->ptr() when we need a \0 terminated string. Use my_strtod() instead of my_atof() to avoid having to add \0 to string. c_ptr() -> c_ptr_safe() to avoid warnings from valgrind. zr sql/event_db_repository.cc: Update usage of TABLE->alias sql/event_scheduler.cc: c_ptr() -> c_ptr_safe() sql/events.cc: c_ptr() -> ptr() as \0 was not needed sql/field.cc: Update usage of TABLE->alias sql/field.h: Update usage of TABLE->alias sql/ha_partition.cc: Update usage of TABLE->alias sql/handler.cc: Update usage of TABLE->alias Fixed wrong usage of str.ptr() sql/item.cc: Fixed error where code wrongly assumed string was \0 terminated. sql/item_func.cc: c_ptr() -> c_ptr_safe() Update usage of TABLE->alias sql/item_sum.h: Use my_strtod() instead of my_atof() to avoid having to add \0 to string sql/lock.cc: Update usage of TABLE->alias sql/log.cc: c_ptr() -> ptr() as \0 was not needed sql/log_event.cc: c_ptr_quick() -> ptr() as \0 was not needed sql/opt_range.cc: ptr() -> c_ptr() as \0 is needed sql/opt_subselect.cc: Update usage of TABLE->alias sql/opt_table_elimination.cc: Update usage of TABLE->alias sql/set_var.cc: ptr() -> c_ptr() as \0 is needed c_ptr() -> c_ptr_safe() sql/sp.cc: c_ptr() -> ptr() as \0 was not needed sql/sp_rcontext.cc: Update usage of TABLE->alias sql/sql_base.cc: Preallocate buffers Update usage of TABLE->alias sql/sql_class.cc: Fix arguments to sprintf() to work even if string is not \0 terminated sql/sql_insert.cc: Update usage of TABLE->alias c_ptr() -> ptr() as \0 was not needed sql/sql_load.cc: Preallocate buffers Trivial optimizations sql/sql_parse.cc: Trivial optimization sql/sql_plugin.cc: c_ptr() -> ptr() as \0 was not needed sql/sql_select.cc: Update usage of TABLE->alias sql/sql_show.cc: Update usage of TABLE->alias sql/sql_string.h: Added move() function to move allocated memory from one object to another. sql/sql_table.cc: Update usage of TABLE->alias c_ptr() -> c_ptr_safe() sql/sql_test.cc: ptr() -> c_ptr_safe() sql/sql_trigger.cc: Update usage of TABLE->alias c_ptr() -> c_ptr_safe() sql/sql_update.cc: Update usage of TABLE->alias sql/sql_view.cc: ptr() -> c_ptr_safe() sql/sql_yacc.yy: ptr() -> c_ptr() sql/table.cc: Update usage of TABLE->alias sql/table.h: Changed TABLE->alias to String to get fewer reallocs when alias are used. storage/federatedx/ha_federatedx.cc: Use c_ptr_safe() to ensure strings are \0 terminated. storage/maria/ha_maria.cc: Update usage of TABLE->alias storage/myisam/ha_myisam.cc: Update usage of TABLE->alias storage/xtradb/row/row0sel.c: Ensure that null bits in record are properly reset. (Old code didn't work as row_search_for_mysql() can be called twice while reading fields from one row. |
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Dmitry Lenev
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6bf6272fda |
Patch that refactors global read lock implementation and fixes
bug #57006 "Deadlock between HANDLER and FLUSH TABLES WITH READ LOCK" and bug #54673 "It takes too long to get readlock for 'FLUSH TABLES WITH READ LOCK'". The first bug manifested itself as a deadlock which occurred when a connection, which had some table open through HANDLER statement, tried to update some data through DML statement while another connection tried to execute FLUSH TABLES WITH READ LOCK concurrently. What happened was that FTWRL in the second connection managed to perform first step of GRL acquisition and thus blocked all upcoming DML. After that it started to wait for table open through HANDLER statement to be flushed. When the first connection tried to execute DML it has started to wait for GRL/the second connection creating deadlock. The second bug manifested itself as starvation of FLUSH TABLES WITH READ LOCK statements in cases when there was a constant stream of concurrent DML statements (in two or more connections). This has happened because requests for protection against GRL which were acquired by DML statements were ignoring presence of pending GRL and thus the latter was starved. This patch solves both these problems by re-implementing GRL using metadata locks. Similar to the old implementation acquisition of GRL in new implementation is two-step. During the first step we block all concurrent DML and DDL statements by acquiring global S metadata lock (each DML and DDL statement acquires global IX lock for its duration). During the second step we block commits by acquiring global S lock in COMMIT namespace (commit code acquires global IX lock in this namespace). Note that unlike in old implementation acquisition of protection against GRL in DML and DDL is semi-automatic. We assume that any statement which should be blocked by GRL will either open and acquires write-lock on tables or acquires metadata locks on objects it is going to modify. For any such statement global IX metadata lock is automatically acquired for its duration. The first problem is solved because waits for GRL become visible to deadlock detector in metadata locking subsystem and thus deadlocks like one in the first bug become impossible. The second problem is solved because global S locks which are used for GRL implementation are given preference over IX locks which are acquired by concurrent DML (and we can switch to fair scheduling in future if needed). Important change: FTWRL/GRL no longer blocks DML and DDL on temporary tables. Before this patch behavior was not consistent in this respect: in some cases DML/DDL statements on temporary tables were blocked while in others they were not. Since the main use cases for FTWRL are various forms of backups and temporary tables are not preserved during backups we have opted for consistently allowing DML/DDL on temporary tables during FTWRL/GRL. Important change: This patch changes thread state names which are used when DML/DDL of FTWRL is waiting for global read lock. It is now either "Waiting for global read lock" or "Waiting for commit lock" depending on the stage on which FTWRL is. Incompatible change: To solve deadlock in events code which was exposed by this patch we have to replace LOCK_event_metadata mutex with metadata locks on events. As result we have to prohibit DDL on events under LOCK TABLES. This patch also adds extensive test coverage for interaction of DML/DDL and FTWRL. Performance of new and old global read lock implementations in sysbench tests were compared. There were no significant difference between new and old implementations. mysql-test/include/check_ftwrl_compatible.inc: Added helper script which allows to check that a statement is compatible with FLUSH TABLES WITH READ LOCK. mysql-test/include/check_ftwrl_incompatible.inc: Added helper script which allows to check that a statement is incompatible with FLUSH TABLES WITH READ LOCK. mysql-test/include/handler.inc: Adjusted test case to the fact that now DROP TABLE closes open HANDLERs for the table to be dropped before checking if there active FTWRL in this connection. mysql-test/include/wait_show_condition.inc: Fixed small error in the timeout message. The correct name of variable used as parameter for this script is "$condition" and not "$wait_condition". mysql-test/r/delayed.result: Added test coverage for scenario which triggered assert in metadata locking subsystem. mysql-test/r/events_2.result: Updated test results after prohibiting event DDL operations under LOCK TABLES. mysql-test/r/flush.result: Added test coverage for bug #57006 "Deadlock between HANDLER and FLUSH TABLES WITH READ LOCK". mysql-test/r/flush_read_lock.result: Added test coverage for various aspects of FLUSH TABLES WITH READ LOCK functionality. mysql-test/r/flush_read_lock_kill.result: Adjusted test case after replacing custom global read lock implementation with one based on metadata locks. Use new debug_sync point. Do not disable concurrent inserts as now InnoDB we always use InnoDB table. mysql-test/r/handler_innodb.result: Adjusted test case to the fact that now DROP TABLE closes open HANDLERs for the table to be dropped before checking if there active FTWRL in this connection. mysql-test/r/handler_myisam.result: Adjusted test case to the fact that now DROP TABLE closes open HANDLERs for the table to be dropped before checking if there active FTWRL in this connection. mysql-test/r/mdl_sync.result: Adjusted test case after replacing custom global read lock implementation with one based on metadata locks. Replaced usage of GRL-specific debug_sync's with appropriate sync points in MDL subsystem. mysql-test/suite/perfschema/r/dml_setup_instruments.result: Updated test results after removing global COND_global_read_lock condition variable. mysql-test/suite/perfschema/r/func_file_io.result: Ensure that this test doesn't affect subsequent tests. At the end of its execution enable back P_S instrumentation which this test disables at some point. mysql-test/suite/perfschema/r/func_mutex.result: Ensure that this test doesn't affect subsequent tests. At the end of its execution enable back P_S instrumentation which this test disables at some point. mysql-test/suite/perfschema/r/global_read_lock.result: Adjusted test case to take into account that new GRL implementation is based on MDL. mysql-test/suite/perfschema/r/server_init.result: Adjusted test case after replacing custom global read lock implementation with one based on MDL and replacing LOCK_event_metadata mutex with metadata lock. mysql-test/suite/perfschema/t/func_file_io.test: Ensure that this test doesn't affect subsequent tests. At the end of its execution enable back P_S instrumentation which this test disables at some point. mysql-test/suite/perfschema/t/func_mutex.test: Ensure that this test doesn't affect subsequent tests. At the end of its execution enable back P_S instrumentation which this test disables at some point. mysql-test/suite/perfschema/t/global_read_lock.test: Adjusted test case to take into account that new GRL implementation is based on MDL. mysql-test/suite/perfschema/t/server_init.test: Adjusted test case after replacing custom global read lock implementation with one based on MDL and replacing LOCK_event_metadata mutex with metadata lock. mysql-test/suite/rpl/r/rpl_tmp_table_and_DDL.result: Updated test results after prohibiting event DDL under LOCK TABLES. mysql-test/t/delayed.test: Added test coverage for scenario which triggered assert in metadata locking subsystem. mysql-test/t/events_2.test: Updated test case after prohibiting event DDL operations under LOCK TABLES. mysql-test/t/flush.test: Added test coverage for bug #57006 "Deadlock between HANDLER and FLUSH TABLES WITH READ LOCK". mysql-test/t/flush_block_commit.test: Adjusted test case after changing thread state name which is used when COMMIT waits for FLUSH TABLES WITH READ LOCK from "Waiting for release of readlock" to "Waiting for commit lock". mysql-test/t/flush_block_commit_notembedded.test: Adjusted test case after changing thread state name which is used when DML waits for FLUSH TABLES WITH READ LOCK. Now we use "Waiting for global read lock" in this case. mysql-test/t/flush_read_lock.test: Added test coverage for various aspects of FLUSH TABLES WITH READ LOCK functionality. mysql-test/t/flush_read_lock_kill-master.opt: We no longer need to use make_global_read_lock_block_commit_loop debug tag in this test. Instead we rely on an appropriate debug_sync point in MDL code. mysql-test/t/flush_read_lock_kill.test: Adjusted test case after replacing custom global read lock implementation with one based on metadata locks. Use new debug_sync point. Do not disable concurrent inserts as now InnoDB we always use InnoDB table. mysql-test/t/lock_multi.test: Adjusted test case after changing thread state names which are used when DML or DDL waits for FLUSH TABLES WITH READ LOCK to "Waiting for global read lock". mysql-test/t/mdl_sync.test: Adjusted test case after replacing custom global read lock implementation with one based on metadata locks. Replaced usage of GRL-specific debug_sync's with appropriate sync points in MDL subsystem. Updated thread state names which are used when DDL waits for FTWRL. mysql-test/t/trigger_notembedded.test: Adjusted test case after changing thread state names which are used when DML or DDL waits for FLUSH TABLES WITH READ LOCK to "Waiting for global read lock". sql/event_data_objects.cc: Removed Event_queue_element::status/last_executed_changed members and Event_queue_element::update_timing_fields() method. We no longer use this class for updating mysql.events once event is chosen for execution. Accesses to instances of this class in scheduler thread require protection by Event_queue::LOCK_event_queue mutex and we try to avoid updating table while holding this lock. sql/event_data_objects.h: Removed Event_queue_element::status/last_executed_changed members and Event_queue_element::update_timing_fields() method. We no longer use this class for updating mysql.events once event is chosen for execution. Accesses to instances of this class in scheduler thread require protection by Event_queue::LOCK_event_queue mutex and we try to avoid updating table while holding this lock. sql/event_db_repository.cc: - Changed Event_db_repository methods to not release all metadata locks once they are done updating mysql.events table. This allows to keep metadata lock protecting against GRL and lock protecting particular event around until corresponding DDL statement is written to the binary log. - Removed logic for conditional update of "status" and "last_executed" fields from update_timing_fields_for_event() method. In the only case when this method is called now "last_executed" is always modified and tracking change of "status" is too much hassle. sql/event_db_repository.h: Removed logic for conditional update of "status" and "last_executed" fields from Event_db_repository:: update_timing_fields_for_event() method. In the only case when this method is called now "last_executed" is always modified and tracking change of "status" field is too much hassle. sql/event_queue.cc: Changed event scheduler code not to update mysql.events table while holding Event_queue::LOCK_event_queue mutex. Doing so led to a deadlock with a new GRL implementation. This deadlock didn't occur with old implementation due to fact that code acquiring protection against GRL ignored pending GRL requests (which lead to GRL starvation). One of goals of new implementation is to disallow GRL starvation and so we have to solve problem with this deadlock in a different way. sql/events.cc: Changed methods of Events class to acquire protection against GRL while perfoming DDL statement and keep it until statement is written to the binary log. Unfortunately this step together with new GRL implementation exposed deadlock involving Events::LOCK_event_metadata and GRL. To solve it Events::LOCK_event_metadata mutex was replaced with a metadata lock on event. As a side-effect events DDL has to be prohibited under LOCK TABLES even in cases when mysql.events table was explicitly locked for write. sql/events.h: Replaced Events::LOCK_event_metadata mutex with a metadata lock on event. sql/ha_ndbcluster.cc: Updated code after replacing custom global read lock implementation with one based on MDL. Since MDL subsystem should now be able to detect deadlocks involving metadata locks and GRL there is no need for special handling of active GRL. sql/handler.cc: Replaced custom implementation of global read lock with one based on metadata locks. Consequently when doing commit instead of calling method of Global_read_lock class to acquire protection against GRL we simply acquire IX in COMMIT namespace. sql/lock.cc: Replaced custom implementation of global read lock with one based on metadata locks. This step allows to expose wait for GRL to deadlock detector of MDL subsystem and thus succesfully resolve deadlocks similar to one behind bug #57006 "Deadlock between HANDLER and FLUSH TABLES WITH READ LOCK". It also solves problem with GRL starvation described in bug #54673 "It takes too long to get readlock for 'FLUSH TABLES WITH READ LOCK'" since metadata locks used by GRL give preference to FTWRL statement instead of DML statements (if needed in future this can be changed to fair scheduling). Similar to old implementation of acquisition of GRL is two-step. During the first step we block all concurrent DML and DDL statements by acquiring global S metadata lock (each DML and DDL statement acquires global IX lock for its duration). During the second step we block commits by acquiring global S lock in COMMIT namespace (commit code acquires global IX lock in this namespace). Note that unlike in old implementation acquisition of protection against GRL in DML and DDL is semi-automatic. We assume that any statement which should be blocked by GRL will either open and acquires write-lock on tables or acquires metadata locks on objects it is going to modify. For any such statement global IX metadata lock is automatically acquired for its duration. To support this change: - Global_read_lock::lock/unlock_global_read_lock and make_global_read_lock_block_commit methods were changed accordingly. - Global_read_lock::wait_if_global_read_lock() and start_waiting_global_read_lock() methods were dropped. It is now responsibility of code acquiring metadata locks opening tables to acquire protection against GRL by explicitly taking global IX lock with statement duration. - Global variables, mutex and condition variable used by old implementation was removed. - lock_routine_name() was changed to use statement duration for its global IX lock. It was also renamed to lock_object_name() as it now also used to take metadata locks on events. - Global_read_lock::set_explicit_lock_duration() was added which allows not to release locks used for GRL when leaving prelocked mode. sql/lock.h: - Renamed lock_routine_name() to lock_object_name() and changed its signature to allow its usage for events. - Removed broadcast_refresh() function. It is no longer needed with new GRL implementation. sql/log_event.cc: Release metadata locks with statement duration at the end of processing legacy event for LOAD DATA. This ensures that replication thread processing such event properly releases its protection against global read lock. sql/mdl.cc: Changed MDL subsystem to support new MDL-based implementation of global read lock. Added COMMIT and EVENTS namespaces for metadata locks. Changed thread state name for GLOBAL namespace to "Waiting for global read lock". Optimized MDL_map::find_or_insert() method to avoid taking m_mutex mutex when looking up MDL_lock objects for GLOBAL or COMMIT namespaces. We keep pre-created MDL_lock objects for these namespaces around and simply return pointers to these global objects when needed. Changed MDL_lock/MDL_scoped_lock to properly handle notification of insert delayed handler threads when FTWRL takes global S lock. Introduced concept of lock duration. In addition to locks with transaction duration which work in the way which is similar to how locks worked before (i.e. they are released at the end of transaction), locks with statement and explicit duration were introduced. Locks with statement duration are automatically released at the end of statement. Locks with explicit duration require explicit release and obsolete concept of transactional sentinel. * Changed MDL_request and MDL_ticket classes to support notion of duration. * Changed MDL_context to keep locks with different duration in different lists. Changed code handling ticket list to take this into account. * Changed methods responsible for releasing locks to take into account duration of tickets. Particularly public MDL_context::release_lock() method now only can release tickets with explicit duration (there is still internal method which allows to specify duration). To release locks with statement or transaction duration one have to use release_statement/transactional_locks() methods. * Concept of savepoint for MDL subsystem now has to take into account locks with statement duration. Consequently MDL_savepoint class was introduced and methods working with savepoints were updated accordingly. * Added methods which allow to set duration for one or all locks in the context. sql/mdl.h: Changed MDL subsystem to support new MDL-based implementation of global read lock. Added COMMIT and EVENTS namespaces for metadata locks. Introduced concept of lock duration. In addition to locks with transaction duration which work in the way which is similar to how locks worked before (i.e. they are released at the end of transaction), locks with statement and explicit duration were introduced. Locks with statement duration are automatically released at the end of statement. Locks with explicit duration require explicit release and obsolete concept of transactional sentinel. * Changed MDL_request and MDL_ticket classes to support notion of duration. * Changed MDL_context to keep locks with different duration in different lists. Changed code handling ticket list to take this into account. * Changed methods responsible for releasing locks to take into account duration of tickets. Particularly public MDL_context::release_lock() method now only can release tickets with explicit duration (there is still internal method which allows to specify duration). To release locks with statement or transaction duration one have to use release_statement/transactional_locks() methods. * Concept of savepoint for MDL subsystem now has to take into account locks with statement duration. Consequently MDL_savepoint class was introduced and methods working with savepoints were updated accordingly. * Added methods which allow to set duration for one or all locks in the context. sql/mysqld.cc: Removed global mutex and condition variables which were used by old implementation of GRL. Also we no longer need to initialize Events::LOCK_event_metadata mutex as it was replaced with metadata locks on events. sql/mysqld.h: Removed global variable, mutex and condition variables which were used by old implementation of GRL. sql/rpl_rli.cc: When slave thread closes tables which were open for handling of RBR events ensure that it releases global IX lock which was acquired as protection against GRL. sql/sp.cc: Adjusted code to the new signature of lock_object/routine_name(), to the fact that one now needs specify duration of lock when initializing MDL_request and to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. sql/sp_head.cc: Ensure that statements in stored procedures release statement metadata locks and thus release their protectiong against GRL in proper moment in time. Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request. sql/sql_admin.cc: Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request. sql/sql_base.cc: - Implemented support for new approach to acquiring protection against global read lock. We no longer acquire such protection explicitly on the basis of statement flags. Instead we always rely on code which is responsible for acquiring metadata locks on object to be changed acquiring this protection. This is achieved by acquiring global IX metadata lock with statement duration. Code doing this also responsible for checking that current connection has no active GRL by calling an Global_read_lock::can_acquire_protection() method. Changed code in open_table() and lock_table_names() accordingly. Note that as result of this change DDL and DML on temporary tables is always compatible with GRL (before it was incompatible in some cases and compatible in other cases). - To speed-up code acquiring protection against GRL introduced m_has_protection_against_grl member in Open_table_context class. It indicates that protection was already acquired sometime during open_tables() execution and new attempts can be skipped. - Thanks to new GRL implementation calls to broadcast_refresh() became unnecessary and were removed. - Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request and to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. sql/sql_base.h: Adjusted code to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. Also introduced Open_table_context::m_has_protection_against_grl member which allows to avoid acquiring protection against GRL while opening tables if such protection was already acquired. sql/sql_class.cc: Changed THD::leave_locked_tables_mode() after transactional sentinel for metadata locks was obsoleted by introduction of locks with explicit duration. sql/sql_class.h: - Adjusted code to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. - Changed Global_read_lock class according to changes in global read lock implementation: * wait_if_global_read_lock and start_waiting_global_read_lock are now gone. Instead code needing protection against GRL has to acquire global IX metadata lock with statement duration itself. To help it new can_acquire_protection() was introduced. Also as result of the above change m_protection_count member is gone too. * Added m_mdl_blocks_commits_lock member to store metadata lock blocking commits. * Adjusted code to the fact that concept of transactional sentinel was obsoleted by concept of lock duration. - Removed CF_PROTECT_AGAINST_GRL flag as it is no longer necessary. New GRL implementation acquires protection against global read lock automagically when statement acquires metadata locks on tables or other objects it is going to change. sql/sql_db.cc: Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request. sql/sql_handler.cc: Removed call to broadcast_refresh() function. It is no longer needed with new GRL implementation. Adjusted code after introducing duration concept for metadata locks. Particularly to the fact transactional sentinel was replaced with explicit duration. sql/sql_handler.h: Renamed mysql_ha_move_tickets_after_trans_sentinel() to mysql_ha_set_explicit_lock_duration() after transactional sentinel was obsoleted by locks with explicit duration. sql/sql_insert.cc: Adjusted code handling delaying inserts after switching to new GRL implementation. Now connection thread initiating delayed insert has to acquire global IX lock in addition to metadata lock on table being inserted into. This IX lock protects against GRL and similarly to SW lock on table being inserted into has to be passed to handler thread in order to avoid deadlocks. sql/sql_lex.cc: LEX::protect_against_global_read_lock member is no longer necessary since protection against GRL is automatically taken by code acquiring metadata locks/opening tables. sql/sql_lex.h: LEX::protect_against_global_read_lock member is no longer necessary since protection against GRL is automatically taken by code acquiring metadata locks/opening tables. sql/sql_parse.cc: - Implemented support for new approach to acquiring protection against global read lock. We no longer acquire such protection explicitly on the basis of statement flags. Instead we always rely on code which is responsible for acquiring metadata locks on object to be changed acquiring this protection. This is achieved by acquiring global IX metadata lock with statement duration. This lock is automatically released at the end of statement execution. - Changed implementation of CREATE/DROP PROCEDURE/FUNCTION not to release metadata locks and thus protection against of GRL in the middle of statement execution. - Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request and to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. sql/sql_prepare.cc: Adjusted code to the to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. sql/sql_rename.cc: With new GRL implementation there is no need to explicitly acquire protection against GRL before renaming tables. This happens automatically in code which acquires metadata locks on tables being renamed. sql/sql_show.cc: Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request and to the fact that savepoints for MDL subsystem are now represented by MDL_savepoint class. sql/sql_table.cc: - With new GRL implementation there is no need to explicitly acquire protection against GRL before dropping tables. This happens automatically in code which acquires metadata locks on tables being dropped. - Changed mysql_alter_table() not to release lock on new table name explicitly and to rely on automatic release of locks at the end of statement instead. This was necessary since now MDL_context::release_lock() is supported only for locks for explicit duration. sql/sql_trigger.cc: With new GRL implementation there is no need to explicitly acquire protection against GRL before changing table triggers. This happens automatically in code which acquires metadata locks on tables which triggers are to be changed. sql/sql_update.cc: Fix bug exposed by GRL testing. During prepare phase acquire only S metadata locks instead of SW locks to keep prepare of multi-UPDATE compatible with concurrent LOCK TABLES WRITE and global read lock. sql/sql_view.cc: With new GRL implementation there is no need to explicitly acquire protection against GRL before creating view. This happens automatically in code which acquires metadata lock on view to be created. sql/sql_yacc.yy: LEX::protect_against_global_read_lock member is no longer necessary since protection against GRL is automatically taken by code acquiring metadata locks/opening tables. sql/table.cc: Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request. sql/table.h: Adjusted code to the fact that one now needs specify duration of lock when initializing MDL_request. sql/transaction.cc: Replaced custom implementation of global read lock with one based on metadata locks. Consequently when doing commit instead of calling method of Global_read_lock class to acquire protection against GRL we simply acquire IX in COMMIT namespace. Also adjusted code to the fact that MDL savepoint is now represented by MDL_savepoint class. |
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Michael Widenius
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20acfbf30d |
Fix for: LP #634955: Assert in _ma_update_at_original_place()
Added locking of lock mutex when updating status in external_unlock() for Aria and MyISAM tables. Fixed that 'source' command doesn't cause mysql command line tool to exit on error. DEBUG_EXECUTE() and DEBUG_EVALUATE_IF() should not execute things based on wildcards. (Allows one to run --debug with mysql-test-run scripts that uses @debug) Fixed several core dump, deadlock and crashed table bugs in handling of LOCK TABLE with MERGE tables: - Added priority of locks to avoid crashes with MERGE tables. - Added thr_lock_merge() to allow one to merge two results of thr_lock(). Fixed 'not found row' bug in REPLACE with Aria tables. Mark MyISAM tables that are part of MERGE with HA_OPEN_MERGE_TABLE and set the locks to have priority THR_LOCK_MERGE_PRIV. - By sorting MERGE tables last in thr_multi_unlock() it's safer to release and relock them many times (can happen when TRIGGERS are created) Avoid printing (null) in debug file (to easier find out wrong NULL pointer usage with %s). client/mysql.cc: Fixed that 'source' command doesn't cause mysql command line tool to exit on error. client/mysqltest.cc: Don't send NULL to fn_format(). (Can cause crash on Solaris when using --debug) dbug/dbug.c: DEBUG_EXECUTE() and DEBUG_EVALUATE_IF() should not execute things based on wildcards. include/my_base.h: Added flag to signal if one opens a MERGE table. Added extra() command to signal that one is not part of a MERGE table anymore. include/thr_lock.h: Added priority for locks (needed to fix bug in thr_lock when using MERGE tables) Added option to thr_unlock() if get_status() should be called. Added prototype for thr_merge_locks(). mysql-test/mysql-test-run.pl: Ignore crashed table warnings for tables named 'crashed'. mysql-test/r/merge.result: Renamed triggers to make debugging easier. Added some CHECK TABLES to catch errors earlier. Additional tests. mysql-test/r/merge_debug.result: Test of error handling when reopening MERGE tables. mysql-test/r/udf_query_cache.result: Added missing flush status mysql-test/suite/parts/r/partition_repair_myisam.result: Update results mysql-test/t/merge.test: Renamed triggers to make debugging easier. Added some CHECK TABLES to catch errors earlier. Additional tests. mysql-test/t/merge_debug.test: Test of error handling when reopening MERGE tables. mysql-test/t/udf_query_cache.test: Added missing flush status mysys/my_getopt.c: Removed not used variable mysys/my_symlink2.c: Changed (null) to (NULL) to make it easier to find NULL arguments to DBUG_PRINT() functions. (On linux, NULL to sprintf is printed 'null') mysys/thr_lock.c: Added priority of locks to avoid crashes with MERGE tables. Added thr_lock_merge() to allow one to merge two results of thr_lock(). - This is needed for MyISAM as all locked table must share the same status. If not, you will not see newly inserted rows in other instances of the table. If calling thr_unlock() with THR_UNLOCK_UPDATE_STATUS, call update_status() and restore_status() for the locks. This is needed in some rare cases where we call thr_unlock() followed by thr_lock() without calling external_unlock/external_lock in between. Simplify loop in thr_multi_lock(). Added 'start_trans', which is called at end of thr_multi_lock() when all locks are taken. - This was needed by Aria to ensure that transaction is started when we got all locks, not at get_status(). Without this, some rows could not be visible when we lock two tables at the same time, causing REPLACE using two tables to fail unexpectedly. sql/handler.cc: Add an assert() in handler::print_error() for "impossible errors" (like table is crashed) when --debug-assert-if-crashed-table is used. sql/lock.cc: Simplify mysql_lock_tables() code if get_lock_data() returns 0 locks. Added new parameter to thr_multi_unlock() In mysql_unlock_read_tables(), call first externa_unlock(), then thr_multi_unlock(); This is same order as we do in mysql_unlock_tables(). Don't abort locks in mysql_lock_abort() for merged tables when a MERGE table is deleted; Would cause a spin lock. Added call to thr_merge_locks() in mysql_lock_merge() to ensure consistency in thr_locks(). - New locks of same type and table is stored after the old lock to ensure that we get the status from the original lock. sql/mysql_priv.h: Added debug_assert_if_crashed_table sql/mysqld.cc: Added --debug-assert-if-crashed-table sql/parse_file.cc: Don't print '(null)' in DBUG_PRINT of no dir given sql/set_var.cc: Increase default size of buffer for @debug variable. sql/sql_base.cc: In case of error from reopen_table() in reopen_tables(), call unlock_open_table() and restart loop. - This fixed bug when we twice deleted same table from open_cache. Don't take name lock for already name locked table in open_unireg_entry(). - Fixed bug when doing repair in reopen_table(). - In detach_merge_children(), always detach if 'clear_refs' is given. We can't trust parent->children_attached as this function can be called twice, first time with clear_refs set to 0. sql/sql_class.cc: Changed printing of (null) to "" in set_thd_proc_info() sql/sql_parse.cc: Added DBUG sql/sql_trigger.cc: Don't call unlink_open_table() if reopen_table() fails as the table may already be freed. storage/maria/ma_bitmap.c: Fixed DBUG_ASSERT() in allocate_tail() storage/maria/ma_blockrec.c: Fixed wrong calculation of row length for very small rows in undo_row_update(). - Fixes ASSERT() when doing undo. storage/maria/ma_blockrec.h: Added _ma_block_start_trans() and _ma_block_start_trans_no_versioning() storage/maria/ma_locking.c: Call _ma_update_status_with_lock() when releasing write locks. - Fixes potential problem with updating status without the proper lock. storage/maria/ma_open.c: Changed to use start_trans() instead of get_status() to ensure that we see all rows in all locked tables when we got the locks. - Fixed 'not found row' bug in REPLACE with Aria tables. storage/maria/ma_state.c: Added _ma_update_status_with_lock() and _ma_block_start_trans(). This is to ensure that we see all rows in all locked tables when we got the locks. storage/maria/ma_state.h: Added _ma_update_status_with_lock() storage/maria/ma_write.c: More DBUG_PRINT storage/myisam/mi_check.c: Fixed error message storage/myisam/mi_extra.c: Added HA_EXTRA_DETACH_CHILD: - Detach MyISAM table to not be part of MERGE table (remove flag & lock priority). storage/myisam/mi_locking.c: Call mi_update_status_with_lock() when releasing write locks. - Fixes potential problem with updating status without the proper lock. Change to use new HA_OPEN_MERGE_TABLE flag to test if MERGE table. Added mi_fix_status(), called by thr_merge(). storage/myisam/mi_open.c: Added marker if part of MERGE table. Call mi_fix_status() in thr_lock() for transactional tables. storage/myisam/myisamdef.h: Change my_once_flag to uint, as it stored different values than just 0/1 Added 'open_flag' to store state given to mi_open() storage/myisammrg/ha_myisammrg.cc: Add THR_LOCK_MERGE_PRIV to THR_LOCK_DATA to get MERGE locks sorted after other types of locks. storage/myisammrg/myrg_locking.c: Remove windows specific code. storage/myisammrg/myrg_open.c: Use HA_OPEN_MERGE_TABLE to mi_open(). Set HA_OPEN_MERGE_TABLE for linked MyISAM tables. storage/xtradb/buf/buf0buf.c: Fixed compiler warning storage/xtradb/buf/buf0lru.c: Initialize variable that could be used not initialized. |
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Davi Arnaut
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2881b8014c |
Bug#37780: Make KILL reliable (main.kill fails randomly)
- A prerequisite cleanup patch for making KILL reliable. The test case main.kill did not work reliably. The following problems have been identified: 1. A kill signal could go lost if it came in, short before a thread went reading on the client connection. 2. A kill signal could go lost if it came in, short before a thread went waiting on a condition variable. These problems have been solved as follows. Please see also added code comments for more details. 1. There is no safe way to detect, when a thread enters the blocking state of a read(2) or recv(2) system call, where it can be interrupted by a signal. Hence it is not possible to wait for the right moment to send a kill signal. It has been decided, not to fix it in the code. Instead, the test case repeats the KILL statement until the connection terminates. 2. Before waiting on a condition variable, we register it together with a synchronizating mutex in THD::mysys_var. After this, we need to test THD::killed again. At some places we did only test it in a loop condition before the registration. When THD::killed had been set between this test and the registration, we entered waiting without noticing the killed flag. Additional checks ahve been introduced where required. In addition to the above, a re-write of the main.kill test case has been done. All sleeps have been replaced by Debug Sync Facility synchronization. A couple of sync points have been added to the server code. To avoid further problems, if the test case fails in spite of the fixes, the test case has been added to the "experimental" list for now. - Most of the work on this patch is authored by Ingo Struewing mysql-test/t/kill.test: Re-wrote test case to use Debug Sync points instead of sleeps sql/event_queue.cc: Fixed kill detection in Event_queue::cond_wait() by adding a check after enter_cond(). sql/lock.cc: Moved Debug Sync points behind enter_cond(). Fixed comments. sql/slave.cc: Fixed kill detection in start_slave_thread() by adding a check after enter_cond(). sql/sql_class.cc: Swapped order of kill and close in THD::awake(). Added comments. sql/sql_class.h: Added a comment to THD::killed. sql/sql_parse.cc: Added a sync point in do_command(). sql/sql_select.cc: Added a sync point in JOIN::optimize(). |
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Davi Arnaut
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3e9c52250a |
Bug#45288: pb2 returns a lot of compilation warnings
Fix assorted warnings that are generated in optimized builds. Most of it is silencing variables that are set but unused. This patch also introduces the MY_ASSERT_UNREACHABLE macro which helps the compiler to deduce that a certain piece of code is unreachable. include/my_compiler.h: Use GCC's __builtin_unreachable if available. It allows GCC to deduce the unreachability of certain code paths, thus avoiding warnings that, for example, accused that a variable could be used without being initialized (due to unreachable code paths). |
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Konstantin Osipov
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29c4873ad5 |
Commit on behalf of Dmitry Lenev.
Merge his patch for Bug#52044 into 5.5, and apply review comments. |
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Dmitry Lenev
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00496b7acd |
Fix for bug #52044 "FLUSH TABLES WITH READ LOCK and FLUSH
TABLES <list> WITH READ LOCK are incompatible". The problem was that FLUSH TABLES <list> WITH READ LOCK which was issued when other connection has acquired global read lock using FLUSH TABLES WITH READ LOCK was blocked and has to wait until global read lock is released. This issue stemmed from the fact that FLUSH TABLES <list> WITH READ LOCK implementation has acquired X metadata locks on tables to be flushed. Since these locks required acquiring of global IX lock this statement was incompatible with global read lock. This patch addresses problem by using SNW metadata type of lock for tables to be flushed by FLUSH TABLES <list> WITH READ LOCK. It is OK to acquire them without global IX lock as long as we won't try to upgrade those locks. Since SNW locks allow concurrent statements using same table FLUSH TABLE <list> WITH READ LOCK now has to wait until old versions of tables to be flushed go away after acquiring metadata locks. Since such waiting can lead to deadlock MDL deadlock detector was extended to take into account waits for flush and resolve such deadlocks. As a bonus code in open_tables() which was responsible for waiting old versions of tables to go away was refactored. Now when we encounter old version of table in open_table() we don't back-off and wait for all old version to go away, but instead wait for this particular table to be flushed. Such approach supported by deadlock detection should reduce number of scenarios in which FLUSH TABLES aborts concurrent multi-statement transactions. Note that active FLUSH TABLES <list> WITH READ LOCK still blocks concurrent FLUSH TABLES WITH READ LOCK statement as the former keeps tables open and thus prevents the latter statement from doing flush. mysql-test/include/handler.inc: Adjusted test case after changing status which is set when FLUSH TABLES waits for tables to be flushed from "Flushing tables" to "Waiting for table". mysql-test/r/flush.result: Added test which checks that "flush tables <list> with read lock" is compatible with active "flush tables with read lock" but not vice-versa. This test also covers bug #52044 "FLUSH TABLES WITH READ LOCK and FLUSH TABLES <list> WITH READ LOCK are incompatible". mysql-test/r/mdl_sync.result: Added scenarios in which wait for table to be flushed causes deadlocks to the coverage of MDL deadlock detector. mysql-test/suite/perfschema/r/dml_setup_instruments.result: Adjusted test results after removal of COND_refresh condition variable. mysql-test/suite/perfschema/r/server_init.result: Adjusted test and its results after removal of COND_refresh condition variable. mysql-test/suite/perfschema/t/server_init.test: Adjusted test and its results after removal of COND_refresh condition variable. mysql-test/t/flush.test: Added test which checks that "flush tables <list> with read lock" is compatible with active "flush tables with read lock" but not vice-versa. This test also covers bug #52044 "FLUSH TABLES WITH READ LOCK and FLUSH TABLES <list> WITH READ LOCK are incompatible". mysql-test/t/kill.test: Adjusted test case after changing status which is set when FLUSH TABLES waits for tables to be flushed from "Flushing tables" to "Waiting for table". mysql-test/t/lock_multi.test: Adjusted test case after changing status which is set when FLUSH TABLES waits for tables to be flushed from "Flushing tables" to "Waiting for table". mysql-test/t/mdl_sync.test: Added scenarios in which wait for table to be flushed causes deadlocks to the coverage of MDL deadlock detector. sql/ha_ndbcluster.cc: Adjusted code after adding one more parameter for close_cached_tables() call - timeout for waiting for table to be flushed. sql/ha_ndbcluster_binlog.cc: Adjusted code after adding one more parameter for close_cached_tables() call - timeout for waiting for table to be flushed. sql/lock.cc: Removed COND_refresh condition variable. See comment for sql_base.cc for details. sql/mdl.cc: Now MDL deadlock detector takes into account information about waits for table flushes when searching for deadlock. To implement this change: - Declaration of enum_deadlock_weight and Deadlock_detection_visitor were moved to mdl.h header to make them available to the code in table.cc which implements deadlock detector traversal through edges of waiters graph representing waiting for flush. - Since now MDL_context may wait not only for metadata lock but also for table to be flushed an abstract Wait_for_edge class was introduced. Its descendants MDL_ticket and Flush_ticket incapsulate specifics of inspecting waiters graph when following through edge representing wait of particular type. We no longer require global IX metadata lock when acquiring SNW or SNRW locks. Such locks are needed only when metadata locks of these types are upgraded to X locks. This allows to use SNW locks in FLUSH TABLES <list> WITH READ LOCK implementation and keep the latter compatible with global read lock. sql/mdl.h: Now MDL deadlock detector takes into account information about waits for table flushes when searching for deadlock. To implement this change: - Declaration of enum_deadlock_weight and Deadlock_detection_visitor were moved to mdl.h header to make them available to the code in table.cc which implements deadlock detector traversal through edges of waiters graph representing waiting for flush. - Since now MDL_context may wait not only for metadata lock but also for table to be flushed an abstract Wait_for_edge class was introduced. Its descendants MDL_ticket and Flush_ticket incapsulate specifics of inspecting waiters graph when following through edge representing wait of particular type. - Deadlock_detection_visitor now has m_table_shares_visited member which allows to support recursive locking for LOCK_open. This is required when deadlock detector inspects waiters graph which contains several edges representing waits for flushes or needs to come through the such edge more than once. sql/mysqld.cc: Removed COND_refresh condition variable. See comment for sql_base.cc for details. sql/mysqld.h: Removed COND_refresh condition variable. See comment for sql_base.cc for details. sql/sql_base.cc: Changed approach to how threads are waiting for table to be flushed. Now thread that wants to wait for old table to go away subscribes for notification by adding Flush_ticket to table's share and waits using MDL_context::m_wait object. Once table gets flushed (i.e. all tables are closed and table share is ready to be destroyed) all such waiters are notified individually. Thanks to this change MDL deadlock detector can take such waits into account. To implement this/as result of this change: - tdc_wait_for_old_versions() was replaced with tdc_wait_for_old_version() which waits for individual old share to go away and which is called by open_table() after finding out that share is outdated. We don't need to perform back-off before such waiting thanks to the fact that deadlock detector now sees such waits. - As result Open_table_ctx::m_mdl_requests became unnecessary and was removed. We no longer allocate copies of MDL_request objects on MEM_ROOT when MYSQL_OPEN_FORCE_SHARED/SHARED_HIGH_PRIO flags are in effect. - close_cached_tables() and tdc_wait_for_old_version() share code which implements waiting for share to be flushed - the both use TABLE_SHARE::wait_until_flush() method. Thanks to this close_cached_tables() supports timeouts and has extra parameter for this. - Open_table_context::OT_MDL_CONFLICT enum element was renamed to OT_CONFLICT as it is now also used in cases when back-off is required to resolve deadlock caused by waiting for flush and not metadata lock. - In cases when we discover that current connection tries to open tables from different generation we now simply back-off and restart process of opening tables. To support this Open_table_context::OT_REOPEN_TABLES enum element was added. - COND_refresh condition variable became unnecessary and was removed. - mysql_notify_thread_having_shared_lock() no longer wakes up connections waiting for flush as all such connections can be waken up by deadlock detector if necessary. sql/sql_base.h: - close_cached_tables() now has one more parameter - timeout for waiting for table to be flushed. - Open_table_context::OT_MDL_CONFLICT enum element was renamed to OT_CONFLICT as it is now also used in cases when back-off is required to resolve deadlock caused by waiting for flush and not metadata lock. Added new OT_REOPEN_TABLES enum element to be used in cases when we need to restart open tables process even in the middle of transaction. - Open_table_ctx::m_mdl_requests became unnecessary and was removed. sql/sql_class.h: Added assert ensuring that we won't use LOCK_open mutex with THD::enter_cond(). Otherwise deadlocks can arise in MDL deadlock detector. sql/sql_parse.cc: Changed FLUSH TABLES <list> WITH READ LOCK to take SNW metadata locks instead of X locks on tables to be flushed. Since we no longer require global IX lock to be taken when SNW locks are taken this makes this statement compatible with FLUSH TABLES WITH READ LOCK statement. Since SNW locks allow other connections to have table opened FLUSH TABLES <list> WITH READ LOCK now has to wait during open_tables() for old version to go away. Such waits can lead to deadlocks which will be detected by MDL deadlock detector which now takes waits for table to be flushed into account. Also adjusted code after adding one more parameter for close_cached_tables() call - timeout for waiting for table to be flushed. sql/sql_yacc.yy: FLUSH TABLES <list> WITH READ LOCK now needs only SNW metadata locks on tables. sql/sys_vars.cc: Adjusted code after adding one more parameter for close_cached_tables() call - timeout for waiting for table to be flushed. sql/table.cc: Implemented new approach to how threads are waiting for table to be flushed. Now thread that wants to wait for old table to go away subscribes for notification by adding Flush_ticket to table's share and waits using MDL_context::m_wait object. Once table gets flushed (i.e. all tables are closed and table share is ready to be destroyed) all such waiters are notified individually. This change allows to make such waits visible inside of MDL deadlock detector. To do it: - Added list of waiters/Flush_tickets to TABLE_SHARE class. - Changed free_table_share() to postpone freeing of share memory until last waiter goes away and to wake up subscribed waiters. - Added TABLE_SHARE::wait_until_flushed() method which implements subscription to the list of waiters for table to be flushed and waiting for this event. Implemented interface which allows to expose waits for flushes to MDL deadlock detector: - Introduced Flush_ticket class a descendant of Wait_for_edge class. - Added TABLE_SHARE::find_deadlock() method which allows deadlock detector to find out what contexts are still using old version of table in question (i.e. to find out what contexts are waited for by owner of Flush_ticket). sql/table.h: In order to support new strategy of waiting for table flush (see comment for table.cc for details) added list of waiters/Flush_tickets to TABLE_SHARE class. Implemented interface which allows to expose waits for flushes to MDL deadlock detector: - Introduced Flush_ticket class a descendant of Wait_for_edge class. - Added TABLE_SHARE::find_deadlock() method which allows deadlock detector to find out what contexts are still using old version of table in question (i.e. to find out what contexts are waited for by owner of Flush_ticket). |
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Konstantin Osipov
|
740c0d3a87 |
Implement WL#5502 Remove dead 5.0 class Sensitive_cursor.
Remove dead and unused code. Update to reflect the code review requests. include/thr_lock.h: Remove declarations for THR_LOCK_OWNER, added along with the patch for sensitive cursors. mysys/thr_lock.c: Remove support for multiple thr_lock requestors per THD. sql/lock.cc: Revert the patch that added support for sensitive cursors. sql/sp_rcontext.cc: Updated the use of mysql_open_cursor(). sql/sql_class.cc: Move the instance of Server_side_cursor from class Prepared_statement to class Statement. sql/sql_class.h: Move the isntance of Server_side_cursor from class Prepared_statement to class Statement. Remove multiple lock_ids of thr_lock. sql/sql_cursor.cc: Remove Sensitive_cursor implementation. sql/sql_cursor.h: Remove declarations for sensitive cursors. sql/sql_prepare.cc: Move the declaration of instance of Server_side_cursor from class Statement to class Prepared_statement, where it's used. sql/sql_select.cc: Remove sensitive cursor support. sql/sql_select.h: Remove sensitive cursor support. sql/sql_union.cc: Remove sensitive cursor support. |
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Jon Olav Hauglid
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f45523188e | merge from mysql-trunk-bugfixing | ||
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Davi Arnaut
|
f56dd32bf7 |
Bug#34043: Server loops excessively in _checkchunk() when safemalloc is enabled
Essentially, the problem is that safemalloc is excruciatingly slow as it checks all allocated blocks for overrun at each memory management primitive, yielding a almost exponential slowdown for the memory management functions (malloc, realloc, free). The overrun check basically consists of verifying some bytes of a block for certain magic keys, which catches some simple forms of overrun. Another minor problem is violation of aliasing rules and that its own internal list of blocks is prone to corruption. Another issue with safemalloc is rather the maintenance cost as the tool has a significant impact on the server code. Given the magnitude of memory debuggers available nowadays, especially those that are provided with the platform malloc implementation, maintenance of a in-house and largely obsolete memory debugger becomes a burden that is not worth the effort due to its slowness and lack of support for detecting more common forms of heap corruption. Since there are third-party tools that can provide the same functionality at a lower or comparable performance cost, the solution is to simply remove safemalloc. Third-party tools can provide the same functionality at a lower or comparable performance cost. The removal of safemalloc also allows a simplification of the malloc wrappers, removing quite a bit of kludge: redefinition of my_malloc, my_free and the removal of the unused second argument of my_free. Since free() always check whether the supplied pointer is null, redudant checks are also removed. Also, this patch adds unit testing for my_malloc and moves my_realloc implementation into the same file as the other memory allocation primitives. client/mysqldump.c: Pass my_free directly as its signature is compatible with the callback type -- which wasn't the case for free_table_ent. |
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Jon Olav Hauglid
|
9ff272fbbd |
A 5.5 version of the fix for Bug #54360 "Deadlock DROP/ALTER/CREATE
DATABASE with open HANDLER" Remove LOCK_create_db, database name locks, and use metadata locks instead. This exposes CREATE/DROP/ALTER DATABASE statements to the graph-based deadlock detector in MDL, and paves the way for a safe, deadlock-free implementation of RENAME DATABASE. Database DDL statements will now take exclusive metadata locks on the database name, while table/view/routine DDL statements take intention exclusive locks on the database name. This prevents race conditions between database DDL and table/view/routine DDL. (e.g. DROP DATABASE with concurrent CREATE/ALTER/DROP TABLE) By adding database name locks, this patch implements WL#4450 "DDL locking: CREATE/DROP DATABASE must use database locks" and WL#4985 "DDL locking: namespace/hierarchical locks". The patch also changes code to use init_one_table() where appropriate. The new lock_table_names() function requires TABLE_LIST::db_length to be set correctly, and this is taken care of by init_one_table(). This patch also adds a simple template to help work with the mysys HASH data structure. Most of the patch was written by Konstantin Osipov. |
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Konstantin Osipov
|
52f361ecb8 |
A fix for Bug#54811 "Assert in mysql_lock_have_duplicate()".
Remove mysql_lock_have_duplicate(), since now we always have TABLE_LIST objects for MyISAMMRG children in lex->query_tables and keep it till the end of the statement (sub-statement). mysql-test/r/merge.result: Update results (Bug#54811). mysql-test/t/merge-big.test: Update to new wait state. mysql-test/t/merge.test: Add a test case for Bug#54811. sql/lock.cc: Remove a function that is now unused. sql/lock.h: Remove a function that is now unused. sql/sql_base.cc: Don't try to search for duplicate table among THR_LOCK objects, TABLE_LIST list contains all used tables. |
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Konstantin Osipov
|
33c57e2f9e |
WL#5419 "LOCK_open scalability: make tdc_refresh_version
an atomic counter" Split the large LOCK_open section in open_table(). Do not call open_table_from_share() under LOCK_open. Remove thd->version. This fixes Bug#50589 "Server hang on a query evaluated using a temporary table" Bug#51557 "LOCK_open and kernel_mutex are not happy together" Bug#49463 "LOCK_table and innodb are not nice when handler instances are created". This patch has effect on storage engines that rely on ha_open() PSEA method being called under LOCK_open. In particular: 1) NDB is broken and left unfixed. NDB relies on LOCK_open being kept as part of ha_open(), since it uses auto-discovery. While previously the NDB open code was race-prone, now it simply fails on asserts. 2) HEAP engine had a race in ha_heap::open() when a share for the same table could be added twice to the list of shares, or a dangling reference to a share stored in HEAP handler. This patch aims to address this problem by 'pinning' the newly created share in the internal HEAP engine share list until at least one handler instance is created using that share. include/heap.h: Add members to HP_CREATE_INFO. Declare heap_release_share(). sql/lock.cc: Remove thd->version, use thd->open_tables->s->version instead. sql/repl_failsafe.cc: Remove thd->version. sql/sql_base.cc: - close_thread_table(): move handler cleanup code outside the critical section protected by LOCK_open. - remove thd->version - split the large critical section in open_table() that opens a new table from share and is protected by LOCK_open into 2 critical sections, thus reducing the critical path. - make check_if_table_exists() acquire LOCK_open internally. - use thd->open_tables->s->version instead of thd->refresh_version to make sure that all tables in thd->open_tables are in the same refresh series. sql/sql_base.h: Add declaration for check_if_table_exists(). sql/sql_class.cc: Remove init_open_tables_state(), it's now equal to reset_open_tables_state(). sql/sql_class.h: Remove thd->version, THD::init_open_tables_state(). sql/sql_plugin.cc: Use table->m_needs_reopen to mark the table as stale rather than manipulate with thd->version, which is no more. sql/sql_udf.cc: Use table->m_needs_reopen to mark the table as stale rather than manipulate with thd->version, which is no more. sql/table.h: Remove an unused variable. sql/tztime.cc: Use table->m_needs_reopen to mark the table as stale rather than manipulate with thd->version, which is no more. storage/heap/CMakeLists.txt: Add heap tests to cmake build files. storage/heap/ha_heap.cc: Fix a race when ha_heap::ha_open() could insert two HP_SHARE objects into the internal share list or store a dangling reference to a share in ha_heap instance, or wrongly set implicit_emptied. storage/heap/hp_create.c: Optionally pin a newly created share in the list of shares by increasing its open_count. This is necessary to make sure that a newly created share doesn't disappear while a HP_INFO object is being created to reference it. storage/heap/hp_open.c: When adding a new HP_INFO object to the list of objects in the heap share, make sure the open_count is not increased twice. storage/heap/hp_test1.c: Adjust the test to new function signatures. storage/heap/hp_test2.c: Adjust the test to new function signatures. |
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Jon Olav Hauglid
|
142a162c66 |
manual merge from mysql-trunk-bugfixing
Conflicts: Text conflict in mysql-test/r/archive.result Contents conflict in mysql-test/r/innodb_bug38231.result Text conflict in mysql-test/r/mdl_sync.result Text conflict in mysql-test/suite/binlog/t/disabled.def Text conflict in mysql-test/suite/rpl_ndb/r/rpl_ndb_binlog_format_errors.result Text conflict in mysql-test/t/archive.test Contents conflict in mysql-test/t/innodb_bug38231.test Text conflict in mysql-test/t/mdl_sync.test Text conflict in sql/sp_head.cc Text conflict in sql/sql_show.cc Text conflict in sql/table.cc Text conflict in sql/table.h |
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Davi Arnaut
|
1164841167 |
Backport: Remove unused and ancient files, functions, and facilities.
client/mysql.cc: Remove unused functions. client/sql_string.cc: Remove unused functions. include/my_pthread.h: Remove unused prototype. mysys/my_pthread.c: Remove unused function. sql/lock.cc: Remove unused function. sql/lock.h: Remove unused and duplicated prototypes. sql/sql_class.h: Removed unused variables. sql/sql_const.h: Remove unused defines. sql/sql_priv.h: Remove unused defines. sql/sql_string.cc: Remove unused prototype. sql/thr_malloc.cc: Remove unused function. sql/thr_malloc.h: Remove unused prototype. storage/myisam/CMakeLists.txt: Remove obsolete fulltext file. storage/myisam/Makefile.am: Remove obsolete files (were already commented out). storage/myisam/ft_eval.c: Remove obsolete fulltext file. storage/myisam/ft_eval.h: Remove obsolete fulltext file. storage/myisam/ft_stem.c: Remove obsolete fulltext file. storage/myisam/ft_test1.c: Remove obsolete fulltext file. storage/myisam/ft_test1.h: Remove obsolete fulltext file. |
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Dmitry Lenev
|
ae1ae4bd63 |
Fix for bug #51263 "Deadlock between transactional
SELECT and ALTER TABLE ... REBUILD PARTITION". ALTER TABLE on InnoDB table (including partitioned tables) acquired exclusive locks on rows of table being altered. In cases when there was concurrent transaction which did locking reads from this table this sometimes led to a deadlock which was not detected by MDL subsystem nor by InnoDB engine (and was reported only after exceeding innodb_lock_wait_timeout). This problem stemmed from the fact that ALTER TABLE acquired TL_WRITE_ALLOW_READ lock on table being altered. This lock was interpreted as a write lock and thus for table being altered handler::external_lock() method was called with F_WRLCK as an argument. As result InnoDB engine treated ALTER TABLE as an operation which is going to change data and acquired LOCK_X locks on rows being read from old version of table. In case when there was a transaction which already acquired SR metadata lock on table and some LOCK_S locks on its rows (e.g. by using it in subquery of DML statement) concurrent ALTER TABLE was blocked at the moment when it tried to acquire LOCK_X lock before reading one of these rows. The transaction's attempt to acquire SW metadata lock on table being altered led to deadlock, since it had to wait for ALTER TABLE to release SNW lock. This deadlock was not detected and got resolved only after timeout expiring because waiting were happening in two different subsystems. Similar deadlocks could have occured in other situations. This patch tries to solve the problem by changing ALTER TABLE implementation to use TL_READ_NO_INSERT lock instead of TL_WRITE_ALLOW_READ. After this step handler::external_lock() is called with F_RDLCK as an argument and InnoDB engine correctly interprets ALTER TABLE as operation which only reads data from original version of table. Thanks to this ALTER TABLE acquires only LOCK_S locks on rows it reads. This, in its turn, causes inter-subsystem deadlocks to go away, as all potential lock conflicts and thus deadlocks will be limited to metadata locking subsystem: - When ALTER TABLE reads rows from table being altered it can't encounter any locks which conflict with LOCK_S row locks. There should be no concurrent transactions holding LOCK_X row locks. Such a transaction should have been acquired SW metadata lock on table first which would have conflicted with ALTER's SNW lock. - Vice versa, when DML which runs concurrently with ALTER TABLE tries to lock row it should be requesting only LOCK_S lock which is compatible with locks acquired by ALTER, as otherwise such DML must own an SW metadata lock on table which would be incompatible with ALTER's SNW lock. mysql-test/r/innodb_mysql_lock2.result: Added test for bug #51263 "Deadlock between transactional SELECT and ALTER TABLE ... REBUILD PARTITION". mysql-test/suite/rpl_ndb/r/rpl_ndb_binlog_format_errors.result: Since CREATE TRIGGER no longer acquires write lock on table it is no longer interpreted as an operation which modifies table data and therefore no longer fails if invoked for SBR-only engine in ROW mode. mysql-test/suite/rpl_ndb/t/rpl_ndb_binlog_format_errors.test: Since CREATE TRIGGER no longer acquires write lock on table it is no longer interpreted as an operation which modifies table data and therefore no longer fails if invoked for SBR-only engine in ROW mode. mysql-test/t/innodb_mysql_lock2.test: Added test for bug #51263 "Deadlock between transactional SELECT and ALTER TABLE ... REBUILD PARTITION". sql/ha_partition.cc: When ALTER TABLE creates a new partition to be filled from other partition lock it in F_WRLCK mode instead of using mode which was used for locking the whole table (it is F_RDLCK now). sql/lock.cc: Replaced conditions which used TL_WRITE_ALLOW_READ lock type with equivalent conditions using TL_WRITE_ALLOW_WRITE. This should allow to get rid of TL_WRITE_ALLOW_READ lock type eventually. sql/mdl.cc: Updated outdated comment to reflect current situation. sql/sql_base.cc: Replaced conditions which used TL_WRITE_ALLOW_READ lock type with equivalent conditions using TL_WRITE_ALLOW_WRITE. This should allow to get rid of TL_WRITE_ALLOW_READ lock type eventually. sql/sql_table.cc: mysql_admin_table(): Use TL_WRITE_ALLOW_WRITE lock type instead of TL_WRITE_ALLOW_READ to determine that we need to acquire upgradable metadata lock. This should allow to completely get rid of TL_WRITE_ALLOW_READ in long term. mysql_recreate_table(): ALTER TABLE now requires TL_READ_NO_INSERT thr_lock.c lock instead of TL_WRITE_ALLOW_READ. sql/sql_trigger.cc: Changed CREATE/DROP TRIGGER implementation to use TL_READ_NO_INSERT lock instead of TL_WRITE_ALLOW_READ lock. The latter is no longer necessary since: a) We now can rely on metadata locks to achieve proper isolation between two DDL statements or DDL and DML statements. b) This statement does not change any data in table so there is no need to inform storage engine about it. sql/sql_yacc.yy: Changed implementation of ALTER TABLE (and CREATE/DROP INDEX as a consequence) to use TL_READ_NO_INSERT lock instead of TL_WRITE_ALLOW_READ lock. This is possible since: a) We now can rely on metadata locks to achieve proper isolation between two DDL statements or DDL and DML statements. b) This statement only reads data in table being open. We write data only to the new version of table and then replace with it old version of table under X metadata lock. Thanks to this change InnoDB will no longer acquire LOCK_X locks on rows being read by ALTER TABLE (instead LOCK_S locks will be acquired) and thus cause of bug #51263 "Deadlock between transactional SELECT and ALTER TABLE ... REBUILD PARTITION" is removed. Did the similar change for CREATE TRIGGER (see comments for sql_trigger.cc for details). |
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Dmitry Lenev
|
bee0f214fd |
Pre-requisite patch for bug #51263 "Deadlock between
transactional SELECT and ALTER TABLE ... REBUILD PARTITION".
The goal of this patch is to decouple type of metadata
lock acquired for table by open_tables() from type of
table-level lock to be acquired on it.
To achieve this we change approach to how we determine what
type of metadata lock should be acquired on table to be open.
Now instead of inferring it at open_tables() time from flags
and type of table-level lock we rely on that type of metadata
lock is properly set at parsing time and is not changed
further.
sql/ha_ndbcluster.cc:
Now one needs to properly initialize table list element's
MDL_request object before calling mysql_rm_table_part2().
sql/lock.cc:
lock_table_names() no longer initializes table list elements'
MDL_request objects. Now proper initialization of these
requests is a responsibility of the caller.
sql/lock.h:
Removed MYSQL_OPEN_TAKE_UPGRADABLE_MDL flag which became
unnecessary. Thanks to the fact that we don't reset type of
requests for metadata locks between re-executions we now can
figure out that upgradable locks are requested by simply
looking at their type which were set in the parser. As result
this flag became redundant.
sql/mdl.h:
Added version of new operator which simplifies allocation of
MDL_request objects on a MEM_ROOT.
sql/sp_head.cc:
Added comment explaining why it is OK to infer type of
metadata lock to request from type of table-level lock
for prelocking.
Added enum_mdl_type argument to sp_add_to_query_tables()
to simplify its usage in trigger implementation.
sql/sp_head.h:
Added enum_mdl_type argument to sp_add_to_query_tables()
to simplify its usage in trigger implementation.
sql/sql_base.cc:
- open_table_get_mdl_lock():
Preserve type of MDL_request for table list element which
was set in the parser by creating MDL_request objects on
memory root if MYSQL_OPEN_FORCE_SHARED_MDL or
MYSQL_OPEN_FORCE_SHARED_HIGH_PRIO_MDL flag were specified.
Thanks to this and to the fact that we no longer reset
type of requests for metadata locks between re-executions
we no longer need to acquire exclusive metadata lock on
table to be created in a special way. This lock is acquired
by code handling acquiring of upgradable locks.
Also changed signature/calling convention for this function
to simplify its usage.
- Accordingly special lock strategy for table list elements
which was used for such locks became unnecessary and was
removed. Other strategies were renamed.
- Since we no longer have guarantee that MDL_request object
which were not satisfied due to lock conflict belongs to
table list element Open_table_context class and its methods
were extended to remember pointer to MDL_request which has
caused problem at request_backoff_action() time and use it
in recover_from_failed_open(). Similar approach is used
for cases when problem from which we need to recover is
not related to MDL but to the table itself. In this case
we store pointer to the element of table list.
- Changed open_tables()/open_tables_check_upgradable_mdl()/
open_tables_acquire_upgradable_mdl() not to rely on
MYSQL_OPEN_TAKE_UPGRADABLE_MDL flag to understand when
upgradable metadata locks should be acquired and not to
infer type of MDL lock from type of table-level lock.
Instead we assume that type of MDL to be acquired was set
in the parser (we can do this as type of MDL_request is
no longer reset between re-executions).
sql/sql_class.h:
Since we no longer have guarantee that MDL_request object
which were not satisfied due to lock conflict belongs to
table list element Open_table_context class and its methods
were extended to remember pointer to MDL_request which has
caused problem at request_backoff_action() time and use it
in recover_from_failed_open(). Similar approach is used
for cases when problem from which we need to recover is
not related to MDL but to the table itself. In this case
we store pointer to the element of table list.
sql/sql_db.cc:
Now one needs to properly initialize table list element's
MDL_request object before calling mysql_rm_table_part2()
or mysql_rename_tables().
sql/sql_lex.cc:
st_select_lex/st_select_lex_node::add_table_to_list() method
now has argument which allows specify type of metadata lock
to be requested for table list element being added.
sql/sql_lex.h:
- st_select_lex/st_select_lex_node::add_table_to_list()
method now has argument which specifies type of metadata
lock to be requested for table list element being added.
This allows to explicitly set type of MDL lock to be
acquired for a DDL statement in parser. It is also more
future-proof than inferring type of MDL request from type
of table-level lock.
- Added Yacc_state::m_mdl_type member which specifies which
type of metadata lock should be requested for tables to be
added to table list by a grammar rule in cases when the same
rule is used in several statements requiring different kinds
of metadata locks.
sql/sql_parse.cc:
- st_select_lex::add_table_to_list() method now has argument
which specifies type of metadata lock to be requested for
table list element being added. This allows to explicitly
set type of MDL lock to be acquired for a DDL statement in
parser. It is also more future-proof than inferring type of
MDL request from type of table-level lock.
- EXCLUSIVE_DOWNGRADABLE_MDL lock strategy has a new name -
OTLS_DOWNGRADE_IF_EXISTS.
- Adjusted LOCK TABLES implementation to the fact that we no
longer infer type of metadata lock to be acquired from table
level lock and that type of MDL request is set at parsing.
And thus MYSQL_OPEN_TAKE_UPGRADABLE_MDL flag became
unnecessary.
sql/sql_prepare.cc:
TABLE_LIST's lock strategy SHARED_MDL was renamed to OTLS_NONE
as now it means that metadata lock should not be changed during
call to open_table() (if it has been already acquired) and is
also used for exclusive metadata lock.
sql/sql_show.cc:
st_select_lex::add_table_to_list() method now has argument
which specifies type of metadata lock to be requested for
table list element being added.
sql/sql_table.cc:
- Adjusted mysql_admin_table()'s code to the fact that
open_tables() no longer determines what kind of metadata
lock should be obtained basing on type of table-level
lock and flags. Instead type of metadata lock for table
to be open should be set before calling open_tables().
- Changed mysql_alter_table() code to the facts:
a) that now it is responsibility of caller to properly
initalize MDL_request in table list elements before calling
lock_table_names()
b) and that MYSQL_OPEN_TAKE_UPGRADABLE_MDL is no longer
necessary since type of metadata lock to be obtained
at open_tables() time is set during parsing.
- Changed code of mysql_recreate_table() to properly set
type of metadata and table-level lock to be obtained
by mysql_alter_table() which it calls.
sql/sql_trigger.cc:
Instead of relying on MYSQL_OPEN_TAKE_UPGRADABLE_MDL flag to
force open_tables() to take an upgradable lock we now specify
exact type of lock to be taken when constructing table list
element for table to be open for CREATE/DROP TRIGGER.
sql/sql_view.cc:
We no longer use TABLE_LIST::EXCLUSIVE_MDL strategy to force
open_tables() to take an exclusive metadata lock on view to
be created. Instead we rely on parser setting proper type of
metadata lock to request and open_tables() acquiring it.
This became possible thanks to the fact that we no longer
reset type of MDL_request between statement re-executions.
sql/sql_yacc.yy:
Instead of inferring type of MDL_request for table to be
open from type of table-level lock and flags passed to
open_tables() we now explicitly specify them at parsing.
This became possible thanks to the fact that we no longer
reset type of MDL_request between statement re-executions.
In future this should allow to decouple type of metadata
lock from type of table-level lock.
The only exception to this approach is statements implemented
through mysql_admin_table() which re-uses same table list
element several times with different types of table-level
and metadata locks.
We now also properly initialize MDL_request objects for table
list elements which are later passed to lock_table_names()
function.
sql/table.cc:
Do not reset type of MDL_request between statement
re-executions. This became unnecessesary as we no longer
change type of MDL_request residing in table list element.
In its turn this change allows to set type of MDL_request
only once - at parsing time.
sql/table.h:
Got rid of TABLE_LIST::EXCLUSIVE_MDL lock strategy.
Now we can specify that we need to acquire exclusive lock
on table to be processed by open_tables() through setting
an appropriate type of MDL_request at parsing time (this
became possible thanks to the fact that we no longer reset
types of MDL_request's belonging to table list elements
between statement re-execution).
Strategy SHARED_MDL was renamed to OTLS_NONE as now it
means that metadata lock should not be changed during call
to open_table() (if it has been already acquired) and is
also used for exclusive metadata lock.
Strategy EXCLUSIVE_DOWNGRADABLE_MDL was renamed to
OTLS_DOWNGRADE_IF_EXISTS.
|
||
|
Mats Kindahl
|
23d8586dbf |
WL#5030: Split and remove mysql_priv.h
This patch: - Moves all definitions from the mysql_priv.h file into header files for the component where the variable is defined - Creates header files if the component lacks one - Eliminates all include directives from mysql_priv.h - Eliminates all circular include cycles - Rename time.cc to sql_time.cc - Rename mysql_priv.h to sql_priv.h |
||
|
Konstantin Osipov
|
09b7a0d115 |
A post-review fix for type-aware metadata locks.
DDL no longer aborts mysql_lock_tables(), and hence we no longer need to support need_reopen flag of this call. Remove the flag, and all the code in the server that was responsible for handling the case when it was set. This allowed to simplify: open_and_lock_tables_derived(), the delayed thread, multi-update. Rename MYSQL_LOCK_IGNORE_FLUSH to MYSQL_OPEN_IGNORE_FLUSH, since we now only support this flag in open_table(). Rename MYSQL_LOCK_PERF_SCHEMA to MYSQL_LOCK_LOG_TABLE, to avoid confusion. Move the wait for the global read lock for cases when we do updates in SELECT f1() or DO (UPDATE) to open_table() from mysql_lock_tables(). When waiting for the read lock, we could raise need_reopen flag, which is no longer present in mysql_lock_tables(). Since the block responsible for waiting for GRL was moved, MYSQL_LOCK_IGNORE_GLOBAL_READ_LOCK was renamed to MYSQL_OPEN_IGNORE_GLOBAL_READ_LOCK. mysql-test/r/mdl_sync.result: Update test results (see comments for mdl_sync.test). mysql-test/t/mdl_sync.test: Update tests: an abort mysql_lock_tables() called for an INSERT no longer auto-closes SQL HANDLERS, since it no longer leads to back-off and retry. sql/ha_ndbcluster_binlog.cc: Remove unused variables. sql/lock.cc: Remove support for need_reopen parameter of mysql_lock_tables(). Update comments. sql/log_event_old.cc: Remove the loop responsible for handling need_reopen out parameter of mysql_lock_tables(). sql/mysql_priv.h: Update open and lock tables flag names. sql/share/errmsg-utf8.txt: Add a new error message to report when thr_multi_lock() is aborted. sql/sql_base.cc: Update comments. Rename MYSQL_LOCK_IGNORE_FLUSH to MYSQL_OPEN_IGNORE_FLUSH. sql/sql_class.h: Remove unused code. sql/sql_db.cc: Remove an unused bit of code. sql/sql_handler.cc: For backward compatibility, we still want to back off and retry when a call to mysql_lock_tables() is aborted from within an SQL HANDLER. Write an internal error handler to support the case. sql/sql_insert.cc: Call mysql_lock_tables() no longer has need_reopen out parameter. Simplify the code by removing the crud that took care of it. MYSQL_LOCK_IGNORE_FLUSH is now only supported by open_tables(). sql/sql_show.cc: Rename MYSQL_LOCK_IGNORE_FLUSH to MYSQL_OPEN_IGNORE_FLUSH sql/sql_table.cc: Remove an unused parameter. sql/sql_update.cc: Remove the need_reopen loop from multi-update. We no also longer need to cleanup the parse tree in case when mysql_lock_tables() is aborted and thus an infinite source of multi-update bugs is gone. sql/tztime.cc: Rename MYSQL_LOCK_IGNORE_FLUSH to MYSQL_OPEN_IGNORE_FLUSH, since from now on this flag is only supported by open_table(). |
||
|
Konstantin Osipov
|
7116431a8a |
A review comment for the fix for Bug#46672.
Remove unnecessary need_reopen loops. |
||
|
Davi Arnaut
|
b11740894e |
Bug#33669: Transactional temporary tables do not work under --read-only
The problem was that in read only mode (read_only enabled), the server would mistakenly deny data modification attempts for temporary tables which belong to a transactional storage engine (eg. InnoDB). The solution is to allow transactional temporary tables to be modified under read only mode. As a whole, the read only mode does not apply to any kind of temporary table. mysql-test/r/read_only_innodb.result: Add test case result for Bug#33669 mysql-test/t/read_only_innodb.test: Add test case for Bug#33669 sql/lock.cc: Rename mysql_lock_tables_check to lock_tables_check and make it static. Move locking related checks from get_lock_data to lock_tables_check. Allow write locks to temporary tables even under read-only. |
||
|
Jon Olav Hauglid
|
e60ef89317 |
Followup to Bug#45225 Locking: hang if drop table with no timeout
This patch prevents system threads and system table accesses from using user-specified values for "lock_wait_timeout". Instead all such accesses are done using the default value (1 year). This prevents background tasks (such as replication, events, accessing stored function definitions, logging, reading time-zone information, etc.) from failing in cases where the global value of "lock_wait_timeout" is set very low. The patch also simplifies the open tables API. Rather than adding another convenience function for opening and locking system tables, this patch removes most of the existing convenience functions for open_and_lock_tables_derived(). Before, open_and_lock_tables() was a convenience function that enforced derived tables handling, while open_and_lock_tables_derived() was the main function where derived tables handling was optional. Now, this convencience function is gone and the main function is renamed to open_and_lock_tables(). No test case added as it would have required the use of --sleep to check that system threads and system tables have a different timeout value from the user-specified "lock_wait_timeout" system variable. |
||
|
Jon Olav Hauglid
|
3d6a89e792 |
Bug #45225 Locking: hang if drop table with no timeout
This patch introduces timeouts for metadata locks. The timeout is specified in seconds using the new dynamic system variable "lock_wait_timeout" which has both GLOBAL and SESSION scopes. Allowed values range from 1 to 31536000 seconds (= 1 year). The default value is 1 year. The new server parameter "lock-wait-timeout" can be used to set the default value parameter upon server startup. "lock_wait_timeout" applies to all statements that use metadata locks. These include DML and DDL operations on tables, views, stored procedures and stored functions. They also include LOCK TABLES, FLUSH TABLES WITH READ LOCK and HANDLER statements. The patch also changes thr_lock.c code (table data locks used by MyISAM and other simplistic engines) to use the same system variable. InnoDB row locks are unaffected. One exception to the handling of the "lock_wait_timeout" variable is delayed inserts. All delayed inserts are executed with a timeout of 1 year regardless of the setting for the global variable. As the connection issuing the delayed insert gets no notification of delayed insert timeouts, we want to avoid unnecessary timeouts. It's important to note that the timeout value is used for each lock acquired and that one statement can take more than one lock. A statement can therefore block for longer than the lock_wait_timeout value before reporting a timeout error. When lock timeout occurs, ER_LOCK_WAIT_TIMEOUT is reported. Test case added to lock_multi.test. include/my_pthread.h: Added macros for comparing two timespec structs. include/thr_lock.h: Introduced timeouts for thr_lock.c locks. mysql-test/r/mysqld--help-notwin.result: Updated result file with the new server variable. mysql-test/r/mysqld--help-win.result: Updated result file with the new server variable. mysql-test/suite/sys_vars/r/lock_wait_timeout_basic.result: Added basic test for the new server variable. mysql-test/suite/sys_vars/t/lock_wait_timeout_basic.test: Added basic test for the new server variable. mysys/thr_lock.c: Introduced timeouts for thr_lock.c locks. sql/mdl.cc: Introduced timeouts for metadata locks. sql/mdl.h: Introduced timeouts for metadata locks. sql/sql_base.cc: Introduced timeouts in tdc_wait_for_old_versions(). sql/sql_class.h: Added new server variable lock_wait_timeout. sql/sys_vars.cc: Added new server variable lock_wait_timeout. |
||
|
Michael Widenius
|
d77e3cde5f |
When one does a drop table, the indexes are not flushed to disk before drop anymore (with MyISAM/Maria)
myisam-recover options changed from OFF to 'DEFAULT' to get less change of data loss when using MyISAM. (The disadvantage is that changed MyISAM tables will be checked at access time; Use --myisam-recover=OFF for old behavior) Don't call extra(HA_EXTRA_FORCE_REOPEN) in ALTER TABLE if table is locked as this will mark table as crashed! Added assert to detect if we accidently would use MyISAM versioning in MySQL include/my_base.h: Mark NOT_USED as USED, as we now use this as a flag to not call extra() mysql-test/mysql-test-run.pl: Don't write all options when there is something wrong with the arguments mysql-test/r/sp-destruct.result: Add missing flush of mysql.proc (as the test copied live tables) mysql-test/r/variables.result: myisam-recover options changed to 'default' mysql-test/r/view.result: Don't show create time in result mysql-test/suite/maria/t/maria-recovery2-master.opt: Don't run test with myisam-recover (as this produces extra warnings during simulated death) mysql-test/t/sp-destruct.test: Add missing flush of mysql.proc (as the test copied live tables) mysql-test/t/view.test: Don't show create time in result sql/lock.cc: Added marker if table was deleted to argument list sql/mysql_priv.h: Added marker if table was deleted to argument list sql/mysqld.cc: myisam-recover options changed from OFF to 'DEFAULT' to get less change of data loss when using MyISAM Allow one to specify OFF as argument to myisam-recover (was default before but one couldn't specify it) sql/sql_base.cc: Mark if table is going to be deleted sql/sql_delete.cc: Mark if table is going to be deleted sql/sql_table.cc: Mark if table is going to be deleted Don't call extra(HA_EXTRA_FORCE_REOPEN) in ALTER TABLE if table is locked as this will mark table as crashed! sql/table.cc: Signal to handler if table is getting deleted as part of getting droped from table cache. sql/table.h: Added marker if table is going to be deleted. storage/maria/ha_maria.cc: Don't search for transaction handler if file is not transactional or outside of transaction (Fixed possible core dump) storage/maria/ma_blockrec.c: Don't write changed information if table is going to be deleted. storage/maria/ma_close.c: Don't write changed information if table is going to be deleted. storage/maria/ma_extra.c: Mark tables that are deleted as crased, to ensure good behavior on restart if we suddenly crash. storage/maria/ma_locking.c: Cleanup storage/maria/ma_recovery.c: We need trnman to be inited during redo phase (to be able to open tables checked with maria_chk) storage/maria/maria_def.h: Added marker if table is going to be deleted. storage/myisam/mi_close.c: Don't write changed information if table is going to be deleted. storage/myisam/mi_extra.c: Mark tables that are deleted as crased, to ensure good behavior on restart if we suddenly crash. storage/myisam/mi_open.c: Added assert to detect if we accidently would use MyISAM versioning in MySQL storage/myisam/myisamdef.h: Added marker if table is going to be deleted. |
||
|
Dmitry Lenev
|
8018ec5adb |
Fix for bug #50913 "Deadlock between open_and_lock_tables_derived
and MDL". Concurrent execution of a multi-DELETE statement and ALTER TABLE statement which affected one of the tables used in the multi-DELETE sometimes led to deadlock. Similar deadlocks might have occured when one performed INSERT/UPDATE/DELETE on a view and concurrently executed ALTER TABLE for the view's underlying table, or when one concurrently executed TRUNCATE TABLE for InnoDB table and ALTER TABLE for the same table. These deadlocks were caused by a discrepancy between types of metadata and thr_lock.cc locks acquired by those statements. What happened was that multi-DELETE/TRUNCATE/DML-through-the- view statement in the first connection acquired SR lock on a table, then ALTER TABLE would come in in the second connection and acquire SNW metadata lock and TL_WRITE_ALLOW_READ thr_lock.c lock and then would start waiting for the first connection during lock upgrade. After that the statement in the first connection would try to acquire TL_WRITE lock on table and would start waiting for the second connection, creating a deadlock. This patch solves this problem by ensuring that we acquire SW metadata lock in all cases in which we acquiring write thr_lock.c lock. This guarantees that deadlocks like the one described above won't occur since all lock conflicts in such situation are resolved within MDL subsystem. This patch also adds assert which should guarantee that such situations won't arise in future. mysql-test/r/lock_multi.result: Added main test for bug #50913 "Deadlock between open_and_lock_tables_derived and MDL". mysql-test/r/mdl_sync.result: Added additional coverage for bug #50913 "Deadlock between open_and_lock_tables_derived and MDL". mysql-test/t/lock_multi.test: Added main test for bug #50913 "Deadlock between open_and_lock_tables_derived and MDL". mysql-test/t/mdl_sync.test: Added additional coverage for bug #50913 "Deadlock between open_and_lock_tables_derived and MDL". sql/lock.cc: Added assert that enforces that when we are locking a non-temporary table we have an appropriate type of metadata lock on this table. sql/mysql_priv.h: Added separate flag for open_tables() to be able specify that SH metadata locks on table to be open should be acquired. We can no longer use MYSQL_LOCK_IGNORE_FLUSH flag for this as in addition to use in I_S implementation it is also used for opening system tables. Since in the latter case we also acquire thr_lock.c locks using SH metadata lock in it instead of SR or SW locks may lead to deadlock. sql/sql_base.cc: When opening tables don't interpret MYSQL_LOCK_IGNORE_FLUSH flag as request to acquire SH metadata locks. This flag is also used for opening system tables for which we also take thr_lock.c locks and thus proper metadata lock to take in this case is SR or SW lock (otherwise deadlocks can occur). In cases when SH lock is really required (e.g. when tables are open by I_S implementation) we rely on that newly introduced MYSQL_OPEN_FORCE_SHARED_HIGH_PRIO_MDL flag is used. sql/sql_delete.cc: mysql_truncate_by_delete(): Adjust type of metadata lock to be requested after changing type of thr_lock.c lock for table list element from one which was set in parser to TL_WRITE. This removes discrepancy between types of these locks which allowed deadlocks to creep in. sql/sql_handler.cc: When closing table which was open by HANDLER statement clear TABLE::open_by_handler flag. This allows to use this flag as a reliable indication that TABLE instance was open by HANDLER statement in assert which was added to mysql_lock_tables(). sql/sql_parse.cc: multi_delete_set_locks_and_link_aux_tables(): Adjust type of metadata lock to be requested after changing type of thr_lock.c lock for table list element from one which was set in parser to TL_WRITE. This removes discrepancy between types of these locks which allowed deadlocks to creep in. sql/sql_show.cc: Use newly introduced MYSQL_OPEN_FORCE_SHARED_HIGH_PRIO_MDL flag in order to acquire SH metadata locks when opening tables in I_S implementation. sql/sql_update.cc: Added comment explaining why in multi-update after deciding that we need weaker thr_lock.c lock on a table we don't downgrade metadata lock on it. sql/sql_view.cc: When merging view into main statement adjust type of metadata lock to be requested after changing type of thr_lock.c lock for table. This removes discrepancy between types of these locks which allowed deadlocks to creep in. |
||
|
Konstantin Osipov
|
a9e22b5896 | Merge next-mr -> next-4284-merge. | ||
|
Konstantin Osipov
|
c8555bdb35 | Merge next-mr -> next-4284 | ||
|
Konstantin Osipov
|
665100b69d | Merge next-mr -> next-4284. | ||
|
Dmitry Lenev
|
eba5d30e67 |
Implement new type-of-operation-aware metadata locks.
Add a wait-for graph based deadlock detector to the MDL subsystem. Fixes bug #46272 "MySQL 5.4.4, new MDL: unnecessary deadlock" and bug #37346 "innodb does not detect deadlock between update and alter table". The first bug manifested itself as an unwarranted abort of a transaction with ER_LOCK_DEADLOCK error by a concurrent ALTER statement, when this transaction tried to repeat use of a table, which it has already used in a similar fashion before ALTER started. The second bug showed up as a deadlock between table-level locks and InnoDB row locks, which was "detected" only after innodb_lock_wait_timeout timeout. A transaction would start using the table and modify a few rows. Then ALTER TABLE would come in, and start copying rows into a temporary table. Eventually it would stumble on the modified records and get blocked on a row lock. The first transaction would try to do more updates, and get blocked on thr_lock.c lock. This situation of circular wait would only get resolved by a timeout. Both these bugs stemmed from inadequate solutions to the problem of deadlocks occurring between different locking subsystems. In the first case we tried to avoid deadlocks between metadata locking and table-level locking subsystems, when upgrading shared metadata lock to exclusive one. Transactions holding the shared lock on the table and waiting for some table-level lock used to be aborted too aggressively. We also allowed ALTER TABLE to start in presence of transactions that modify the subject table. ALTER TABLE acquires TL_WRITE_ALLOW_READ lock at start, and that block all writes against the table (naturally, we don't want any writes to be lost when switching the old and the new table). TL_WRITE_ALLOW_READ lock, in turn, would block the started transaction on thr_lock.c lock, should they do more updates. This, again, lead to the need to abort such transactions. The second bug occurred simply because we didn't have any mechanism to detect deadlocks between the table-level locks in thr_lock.c and row-level locks in InnoDB, other than innodb_lock_wait_timeout. This patch solves both these problems by moving lock conflicts which are causing these deadlocks into the metadata locking subsystem, thus making it possible to avoid or detect such deadlocks inside MDL. To do this we introduce new type-of-operation-aware metadata locks, which allow MDL subsystem to know not only the fact that transaction has used or is going to use some object but also what kind of operation it has carried out or going to carry out on the object. This, along with the addition of a special kind of upgradable metadata lock, allows ALTER TABLE to wait until all transactions which has updated the table to go away. This solves the second issue. Another special type of upgradable metadata lock is acquired by LOCK TABLE WRITE. This second lock type allows to solve the first issue, since abortion of table-level locks in event of DDL under LOCK TABLES becomes also unnecessary. Below follows the list of incompatible changes introduced by this patch: - From now on, ALTER TABLE and CREATE/DROP TRIGGER SQL (i.e. those statements that acquire TL_WRITE_ALLOW_READ lock) wait for all transactions which has *updated* the table to complete. - From now on, LOCK TABLES ... WRITE, REPAIR/OPTIMIZE TABLE (i.e. all statements which acquire TL_WRITE table-level lock) wait for all transaction which *updated or read* from the table to complete. As a consequence, innodb_table_locks=0 option no longer applies to LOCK TABLES ... WRITE. - DROP DATABASE, DROP TABLE, RENAME TABLE no longer abort statements or transactions which use tables being dropped or renamed, and instead wait for these transactions to complete. - Since LOCK TABLES WRITE now takes a special metadata lock, not compatible with with reads or writes against the subject table and transaction-wide, thr_lock.c deadlock avoidance algorithm that used to ensure absence of deadlocks between LOCK TABLES WRITE and other statements is no longer sufficient, even for MyISAM. The wait-for graph based deadlock detector of MDL subsystem may sometimes be necessary and is involved. This may lead to ER_LOCK_DEADLOCK error produced for multi-statement transactions even if these only use MyISAM: session 1: session 2: begin; update t1 ... lock table t2 write, t1 write; -- gets a lock on t2, blocks on t1 update t2 ... (ER_LOCK_DEADLOCK) - Finally, support of LOW_PRIORITY option for LOCK TABLES ... WRITE was abandoned. LOCK TABLE ... LOW_PRIORITY WRITE from now on has the same priority as the usual LOCK TABLE ... WRITE. SELECT HIGH PRIORITY no longer trumps LOCK TABLE ... WRITE in the wait queue. - We do not take upgradable metadata locks on implicitly locked tables. So if one has, say, a view v1 that uses table t1, and issues: LOCK TABLE v1 WRITE; FLUSH TABLE t1; -- (or just 'FLUSH TABLES'), an error is produced. In order to be able to perform DDL on a table under LOCK TABLES, the table must be locked explicitly in the LOCK TABLES list. mysql-test/include/handler.inc: Adjusted test case to trigger an execution path on which bug 41110 "crash with handler command when used concurrently with alter table" and bug 41112 "crash in mysql_ha_close_table/get_lock_data with alter table" were originally discovered. Left old test case which no longer triggers this execution path for the sake of coverage. Added test coverage for HANDLER SQL statements and type-aware metadata locks. Added a test for the global shared lock and HANDLER SQL. Updated tests to take into account that the old simple deadlock detection heuristics was replaced with a graph-based deadlock detector. mysql-test/r/debug_sync.result: Updated results (see debug_sync.test). mysql-test/r/handler_innodb.result: Updated results (see handler.inc test). mysql-test/r/handler_myisam.result: Updated results (see handler.inc test). mysql-test/r/innodb-lock.result: Updated results (see innodb-lock.test). mysql-test/r/innodb_mysql_lock.result: Updated results (see innodb_mysql_lock.test). mysql-test/r/lock.result: Updated results (see lock.test). mysql-test/r/lock_multi.result: Updated results (see lock_multi.test). mysql-test/r/lock_sync.result: Updated results (see lock_sync.test). mysql-test/r/mdl_sync.result: Updated results (see mdl_sync.test). mysql-test/r/sp-threads.result: SHOW PROCESSLIST output has changed due to the fact that waiting for LOCK TABLES WRITE now happens within metadata locking subsystem. mysql-test/r/truncate_coverage.result: Updated results (see truncate_coverage.test). mysql-test/suite/funcs_1/datadict/processlist_val.inc: SELECT FROM I_S.PROCESSLIST output has changed due to fact that waiting for LOCK TABLES WRITE now happens within metadata locking subsystem. mysql-test/suite/funcs_1/r/processlist_val_no_prot.result: SELECT FROM I_S.PROCESSLIST output has changed due to fact that waiting for LOCK TABLES WRITE now happens within metadata locking subsystem. mysql-test/suite/rpl/t/rpl_sp.test: Updated to a new SHOW PROCESSLIST state name. mysql-test/t/debug_sync.test: Use LOCK TABLES READ instead of LOCK TABLES WRITE as the latter no longer allows to trigger execution path involving waiting on thr_lock.c lock and therefore reaching debug sync-point covered by this test. mysql-test/t/innodb-lock.test: Adjusted test case to the fact that innodb_table_locks=0 option is no longer supported, since LOCK TABLES WRITE handles all its conflicts within MDL subsystem. mysql-test/t/innodb_mysql_lock.test: Added test for bug #37346 "innodb does not detect deadlock between update and alter table". mysql-test/t/lock.test: Added test coverage which checks the fact that we no longer support DDL under LOCK TABLES on tables which were locked implicitly. Adjusted existing test cases accordingly. mysql-test/t/lock_multi.test: Added test for bug #46272 "MySQL 5.4.4, new MDL: unnecessary deadlock". Adjusted other test cases to take into account the fact that waiting for LOCK TABLES ... WRITE now happens within MDL subsystem. mysql-test/t/lock_sync.test: Since LOCK TABLES ... WRITE now takes SNRW metadata lock for tables locked explicitly we have to implicitly lock InnoDB tables (through view) to trigger the table-level lock conflict between TL_WRITE and TL_WRITE_ALLOW_WRITE. mysql-test/t/mdl_sync.test: Added basic test coverage for type-of-operation-aware metadata locks. Also covered with tests some use cases involving HANDLER statements in which a deadlock could arise. Adjusted existing tests to take type-of-operation-aware MDL into account. mysql-test/t/multi_update.test: Update to a new SHOW PROCESSLIST state name. mysql-test/t/truncate_coverage.test: Adjusted test case after making LOCK TABLES WRITE to wait until transactions that use the table to be locked are completed. Updated to the changed name of DEBUG_SYNC point. sql/handler.cc: Global read lock functionality has been moved into a class. sql/lock.cc: Global read lock functionality has been moved into a class. Updated code to use the new MDL API. sql/mdl.cc: Introduced new type-of-operation aware metadata locks. To do this: - Changed MDL_lock to use one list for waiting requests and one list for granted requests. For each list, added a bitmap that holds information what lock types a list contains. Added a helper class MDL_lock::List to manipulate with granted and waited lists while keeping the bitmaps in sync with list contents. - Changed lock-compatibility functions to use bitmaps that define compatibility. - Introduced a graph based deadlock detector inspired by waiting_threads.c from Maria implementation. - Now that we have a deadlock detector, and no longer have a global lock to protect individual lock objects, but rather use an rw lock per object, removed redundant code for upgrade, and the global read lock. Changed the MDL API to no longer require the caller to acquire the global intention exclusive lock by means of a separate method. Removed a few more methods that became redundant. - Removed deadlock detection heuristic, it has been made obsolete by the deadlock detector. - With operation-type-aware metadata locks, MDL subsystem has become aware of potential conflicts between DDL and open transactions. This made it possible to remove calls to mysql_abort_transactions_with_shared_lock() from acquisition paths for exclusive lock and lock upgrade. Now we can simply wait for these transactions to complete without fear of deadlock. Function mysql_lock_abort() has also become unnecessary for all conflicting cases except when a DDL conflicts with a connection that has an open HANDLER. sql/mdl.h: Introduced new type-of-operation aware metadata locks. Introduced a graph based deadlock detector and supporting methods. Added comments. God rid of redundant API calls. Renamed m_lt_or_ha_sentinel to m_trans_sentinel, since now it guards the global read lock as well as LOCK TABLES and HANDLER locks. sql/mysql_priv.h: Moved the global read lock functionality into a class. Added MYSQL_OPEN_FORCE_SHARED_MDL flag which forces open_tables() to take MDL_SHARED on tables instead of metadata locks specified in the parser. We use this to allow PREPARE run concurrently in presence of LOCK TABLES ... WRITE. Added signature for find_table_for_mdl_ugprade(). sql/set_var.cc: Global read lock functionality has been moved into a class. sql/sp_head.cc: When creating TABLE_LIST elements for prelocking or system tables set the type of request for metadata lock according to the operation that will be performed on the table. sql/sql_base.cc: - Updated code to use the new MDL API. - In order to avoid locks starvation we take upgradable locks all at once. As result implicitly locked tables no longer get an upgradable lock. Consequently DDL and FLUSH TABLES for such tables is prohibited. find_write_locked_table() was replaced by find_table_for_mdl_upgrade() function. open_table() was adjusted to return TABLE instance with upgradable ticket when necessary. - We no longer wait for all locks on OT_WAIT back off action -- only on the lock that caused the wait conflict. Moreover, now we distinguish cases when we have to wait due to conflict in MDL and old version of table in TDC. - Upate mysql_notify_threads_having_share_locks() to only abort thr_lock.c waits of threads that have open HANDLERs, since lock conflicts with only these threads now can lead to deadlocks not detectable by the MDL deadlock detector. - Remove mysql_abort_transactions_with_shared_locks() which is no longer needed. sql/sql_class.cc: Global read lock functionality has been moved into a class. Re-arranged code in THD::cleanup() to simplify assert. sql/sql_class.h: Introduced class to incapsulate global read lock functionality. Now sentinel in MDL subsystem guards the global read lock as well as LOCK TABLES and HANDLER locks. Adjusted code accordingly. sql/sql_db.cc: Global read lock functionality has been moved into a class. sql/sql_delete.cc: We no longer acquire upgradable metadata locks on tables which are locked by LOCK TABLES implicitly. As result TRUNCATE TABLE is no longer allowed for such tables. Updated code to use the new MDL API. sql/sql_handler.cc: Inform MDL_context about presence of open HANDLERs. Since HANLDERs break MDL protocol by acquiring table-level lock while holding only S metadata lock on a table MDL subsystem should take special care about such contexts (Now this is the only case when mysql_lock_abort() is used). sql/sql_parse.cc: Global read lock functionality has been moved into a class. Do not take upgradable metadata locks when opening tables for CREATE TABLE SELECT as it is not necessary and limits concurrency. When initializing TABLE_LIST objects before adding them to the table list set the type of request for metadata lock according to the operation that will be performed on the table. We no longer acquire upgradable metadata locks on tables which are locked by LOCK TABLES implicitly. As result FLUSH TABLES is no longer allowed for such tables. sql/sql_prepare.cc: Use MYSQL_OPEN_FORCE_SHARED_MDL flag when opening tables during PREPARE. This allows PREPARE to run concurrently in presence of LOCK TABLES ... WRITE. sql/sql_rename.cc: Global read lock functionality has been moved into a class. sql/sql_show.cc: Updated code to use the new MDL API. sql/sql_table.cc: Global read lock functionality has been moved into a class. We no longer acquire upgradable metadata locks on tables which are locked by LOCK TABLES implicitly. As result DROP TABLE is no longer allowed for such tables. Updated code to use the new MDL API. sql/sql_trigger.cc: Global read lock functionality has been moved into a class. We no longer acquire upgradable metadata locks on tables which are locked by LOCK TABLES implicitly. As result CREATE/DROP TRIGGER is no longer allowed for such tables. Updated code to use the new MDL API. sql/sql_view.cc: Global read lock functionality has been moved into a class. Fixed results of wrong merge that led to misuse of GLR API. CREATE VIEW statement is not a commit statement. sql/table.cc: When resetting TABLE_LIST objects for PS or SP re-execution set the type of request for metadata lock according to the operation that will be performed on the table. Do the same in auxiliary function initializing metadata lock requests in a table list. sql/table.h: When initializing TABLE_LIST objects set the type of request for metadata lock according to the operation that will be performed on the table. sql/transaction.cc: Global read lock functionality has been moved into a class. |
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Dmitry Lenev
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6ddd01c27a |
Patch that changes metadata locking subsystem to use mutex per lock and
condition variable per context instead of one mutex and one conditional variable for the whole subsystem. This should increase concurrency in this subsystem. It also opens the way for further changes which are necessary to solve such bugs as bug #46272 "MySQL 5.4.4, new MDL: unnecessary deadlock" and bug #37346 "innodb does not detect deadlock between update and alter table". Two other notable changes done by this patch: - MDL subsystem no longer implicitly acquires global intention exclusive metadata lock when per-object metadata lock is acquired. Now this has to be done by explicit calls outside of MDL subsystem. - Instead of using separate MDL_context for opening system tables/tables for purposes of I_S we now create MDL savepoint in the main context before opening tables and rollback to this savepoint after closing them. This means that it is now possible to get ER_LOCK_DEADLOCK error even not inside a transaction. This might happen in unlikely case when one runs DDL on one of system tables while also running DDL on some other tables. Cases when this ER_LOCK_DEADLOCK error is not justified will be addressed by advanced deadlock detector for MDL subsystem which we plan to implement. mysql-test/include/handler.inc: Adjusted handler_myisam.test and handler_innodb.test to the fact that exclusive metadata locks on tables are now acquired according to alphabetical order of fully qualified table names instead of order in which tables are mentioned in statement. mysql-test/r/handler_innodb.result: Adjusted handler_myisam.test and handler_innodb.test to the fact that exclusive metadata locks on tables are now acquired according to alphabetical order of fully qualified table names instead of order in which tables are mentioned in statement. mysql-test/r/handler_myisam.result: Adjusted handler_myisam.test and handler_innodb.test to the fact that exclusive metadata locks on tables are now acquired according to alphabetical order of fully qualified table names instead of order in which tables are mentioned in statement. mysql-test/r/mdl_sync.result: Adjusted mdl_sync.test to the fact that exclusive metadata locks on tables are now acquired according to alphabetical order of fully qualified table names instead of order in which tables are mentioned in statement. mysql-test/t/mdl_sync.test: Adjusted mdl_sync.test to the fact that exclusive metadata locks on tables are now acquired according to alphabetical order of fully qualified table names instead of order in which tables are mentioned in statement. sql/events.cc: Instead of using separate MDL_context for opening system tables we now create MDL savepoint in the main context before opening such tables and rollback to this savepoint after closing them. To support this change methods of THD responsible for saving/restoring open table state were changed to use Open_tables_backup class which in addition to Open_table_state has a member for this savepoint. As result code opening/closing system tables was changed to use Open_tables_backup instead of Open_table_state class as well. sql/ha_ndbcluster.cc: Since manipulations with open table state no longer install proxy MDL_context it does not make sense to perform them in order to satisfy assert in mysql_rm_tables_part2(). Removed them per agreement with Cluster team. This has not broken test suite since scenario in which deadlock can occur and assertion fails is not covered by tests. sql/lock.cc: MDL subsystem no longer implicitly acquires global intention exclusive metadata lock when per-object exclusive metadata lock is acquired. Now this has to be done by explicit calls outside of MDL subsystem. sql/log.cc: Instead of using separate MDL_context for opening system tables we now create MDL savepoint in the main context before opening such tables and rollback to this savepoint after closing them. To support this change methods of THD responsible for saving/restoring open table state were changed to use Open_tables_backup class which in addition to Open_table_state has a member for this savepoint. As result code opening/closing system tables was changed to use Open_tables_backup instead of Open_table_state class as well. sql/mdl.cc: Changed metadata locking subsystem to use mutex per lock and condition variable per context instead of one mutex and one conditional variable for the whole subsystem. Changed approach to handling of global metadata locks. Instead of implicitly acquiring intention exclusive locks when user requests per-object upgradeable or exclusive locks now we require them to be acquired explicitly in the same way as ordinary metadata locks. In fact global lock are now ordinary metadata locks in new GLOBAL namespace. To implement these changes: - Removed LOCK_mdl mutex and COND_mdl condition variable. - Introduced MDL_lock::m_mutex mutexes which protect individual lock objects. - Replaced mdl_locks hash with MDL_map class, which has hash for MDL_lock objects as a member and separate mutex which protects this hash. Methods of this class allow to find(), find_or_create() or remove() MDL_lock objects in concurrency-friendly fashion (i.e. for most common operation, find_or_create(), we don't acquire MDL_lock::m_mutex while holding MDL_map::m_mutex. Thanks to MikaelR for this idea and benchmarks!). Added three auxiliary members to MDL_lock class (m_is_destroyed, m_ref_usage, m_ref_release) to support this concurrency-friendly behavior. - Introduced MDL_context::m_ctx_wakeup_cond condition variable to be used for waiting until this context's pending request can be satisfied or its thread has to perform actions to resolve potential deadlock. Context which want to wait add ticket corresponding to the request to an appropriate queue of waiters in MDL_lock object so they can be noticed when other contexts change state of lock and be awaken by them by signalling on MDL_context::m_ctx_wakeup_cond. As consequence MDL_ticket objects has to be used for any waiting in metadata locking subsystem including one which happens in MDL_context::wait_for_locks() method. Another consequence is that MDL_context is no longer copyable and can't be saved/restored when working with system tables. - Made MDL_lock an abstract class, which delegates specifying exact compatibility matrix to its descendants. Added MDL_global_lock child class for global lock (The old is_lock_type_compatible() method became can_grant_lock() method of this class). Added MDL_object_lock class to represent per-object lock (The old MDL_lock::can_grant_lock() became its method). Choice between two classes happens based on MDL namespace in MDL_lock::create() method. - Got rid of MDL_lock::type member as its meaning became ambigous for global locks. - To simplify waking up of contexts waiting for lock split waiting queue in MDL_lock class in two queues. One for pending requests for exclusive (including intention exclusive) locks and another for requests for shared locks. - Added virtual wake_up_waiters() method to MDL_lock, MDL_global_lock and MDL_object_lock classes which allows to wake up waiting contexts after state of lock changes. Replaced old duplicated code with calls to this method. - Adjusted MDL_context::try_acquire_shared_lock()/exclusive_lock()/ global_shared_lock(), MDL_ticket::upgrade_shared_lock_to_exclusive_lock() and MDL_context::release_ticket() methods to use MDL_map and MDL_lock::m_mutex instead of single LOCK_mdl mutex and wake up waiters according to the approach described above. The latter method also was renamed to MDL_context::release_lock(). - Changed MDL_context::try_acquire_shared_lock()/exclusive_lock() and release_lock() not to handle global locks. They are now supposed to be taken explicitly like ordinary metadata locks. - Added helper MDL_context::try_acquire_global_intention_exclusive_lock() and acquire_global_intention_exclusive_lock() methods. - Moved common code from MDL_context::acquire_global_shared_lock() and acquire_global_intention_exclusive_lock() to new method - MDL_context::acquire_lock_impl(). - Moved common code from MDL_context::try_acquire_shared_lock(), try_acquire_global_intention_exclusive_lock()/exclusive_lock() to MDL_context::try_acquire_lock_impl(). - Since acquiring of several exclusive locks can no longer happen under single LOCK_mdl mutex the approach to it had to be changed. Now we do it in one by one fashion. This is done in alphabetical order to avoid deadlocks. Changed MDL_context::acquire_exclusive_locks() accordingly (as part of this change moved code responsible for acquiring single exclusive lock to new MDL_context::acquire_exclusive_lock_impl() method). - Since we no longer have single LOCK_mdl mutex which protects all MDL_context::m_is_waiting_in_mdl members using these members to determine if we have really awaken context holding conflicting shared lock became inconvinient. Got rid of this member and changed notify_shared_lock() helper function and process of acquiring of/upgrading to exclusive lock not to rely on such information. Now in MDL_context::acquire_exclusive_lock_impl() and MDL_ticket::upgrade_shared_lock_to_exclusive_lock() we simply re-try to wake up threads holding conflicting shared locks after small time out. - Adjusted MDL_context::can_wait_lead_to_deadlock() and MDL_ticket::has_pending_conflicting_lock() to use per-lock mutexes instead of LOCK_mdl. To do this introduced MDL_lock::has_pending_exclusive_lock() method. sql/mdl.h: Changed metadata locking subsystem to use mutex per lock and condition variable per context instead of one mutex and one conditional variable for the whole subsystem. In order to implement this change: - Added MDL_key::cmp() method to be able to sort MDL_key objects alphabetically. Changed length fields in MDL_key class to uint16 as 16-bit is enough for length of any key. - Changed MDL_ticket::get_ctx() to return pointer to non-const object in order to be able to use MDL_context::awake() method for such contexts. - Got rid of unlocked versions of can_wait_lead_to_deadlock()/ has_pending_conflicting_lock() methods in MDL_context and MDL_ticket. We no longer has single mutex which protects all locks. Thus one always has to use versions of these methods which acquire per-lock mutexes. - MDL_request_list type of list now counts its elements. - Added MDL_context::m_ctx_wakeup_cond condition variable to be used for waiting until this context's pending request can be satisfied or its thread has to perform actions to resolve potential deadlock. Added awake() method to wake up context from such wait. Addition of condition variable made MDL_context uncopyable. As result we no longer can save/restore MDL_context when working with system tables. Instead we create MDL savepoint before opening those tables and rollback to it once they are closed. - MDL_context::release_ticket() became release_lock() method. - Added auxiliary MDL_context::acquire_exclusive_lock_impl() method which does all necessary work to acquire exclusive lock on one object but should not be used directly as it does not enforce any asserts ensuring that no deadlocks are possible. - Since we no longer need to know if thread trying to acquire exclusive lock managed to wake up any threads having conflicting shared locks (as, anyway, we will try to wake up such threads again shortly) - MDL_context::m_is_waiting_in_mdl member became unnecessary and notify_shared_lock() no longer needs to be friend of MDL_context. Changed approach to handling of global metadata locks. Instead of implicitly acquiring intention exclusive locks when user requests per-object upgradeable or exclusive locks now we require them to be acquired explicitly in the same way as ordinary metadata locks. - Added new GLOBAL namespace for such locks. - Added new type of lock to be requested MDL_INTENTION_EXCLISIVE. - Added MDL_context::try_acquire_global_intention_exclusive_lock() and acquire_global_intention_exclusive_lock() methods. - Moved common code from MDL_context::acquire_global_shared_lock() and acquire_global_intention_exclusive_lock() to new method - MDL_context::acquire_lock_impl(). - Moved common code from MDL_context::try_acquire_shared_lock(), try_acquire_global_intention_exclusive_lock()/exclusive_lock() to MDL_context::try_acquire_lock_impl(). - Added helper MDL_context::is_global_lock_owner() method to be able easily to find what kind of global lock this context holds. - MDL_context::m_has_global_shared_lock became unnecessary as global read lock is now represented by ordinary ticket. - Removed assert in MDL_context::set_lt_or_ha_sentinel() which became false for cases when we execute LOCK TABLES under global read lock mode. sql/mysql_priv.h: Instead of using separate MDL_context for opening system tables we now create MDL savepoint in the main context before opening such tables and rollback to this savepoint after closing them. To support this change methods of THD responsible for saving/restoring open table state were changed to use Open_tables_backup class which in addition to Open_table_state has a member for this savepoint. As result calls opening/closing system tables were changed to use Open_tables_backup instead of Open_table_state class as well. sql/sp.cc: Instead of using separate MDL_context for opening system tables we now create MDL savepoint in the main context before opening such tables and rollback to this savepoint after closing them. To support this change methods of THD responsible for saving/restoring open table state were changed to use Open_tables_backup class which in addition to Open_table_state has a member for this savepoint. As result code opening/closing system tables was changed to use Open_tables_backup instead of Open_table_state class as well. sql/sp.h: Instead of using separate MDL_context for opening system tables we now create MDL savepoint in the main context before opening such tables and rollback to this savepoint after closing them. To support this change methods of THD responsible for saving/restoring open table state were changed to use Open_tables_backup class which in addition to Open_table_state has a member for this savepoint. As result code opening/closing system tables was changed to use Open_tables_backup instead of Open_table_state class as well. sql/sql_base.cc: close_thread_tables(): Since we no longer use separate MDL_context for opening system tables we need to avoid releasing all transaction locks when closing system table. Releasing metadata lock on system table is now responsibility of THD::restore_backup_open_tables_state(). open_table_get_mdl_lock(), Open_table_context::recover_from_failed_open(): MDL subsystem no longer implicitly acquires global intention exclusive metadata lock when per-object upgradable or exclusive metadata lock is acquired. So this have to be done explicitly from these calls. Changed Open_table_context class to store MDL_request object for global intention exclusive lock acquired when opening tables. open_table(): Do not release metadata lock if we have failed to open table as this lock might have been acquired by one of previous statements in transaction, and therefore should not be released. open_system_tables_for_read()/close_system_tables()/ open_performance_schema_table(): Instead of using separate MDL_context for opening system tables we now create MDL savepoint in the main context before opening such tables and rollback to this savepoint after closing them. To support this change methods of THD responsible for saving/restoring open table state were changed to use Open_tables_backup class which in addition to Open_table_state has a member for this savepoint. As result code opening/closing system tables was changed to use Open_tables_backup instead of Open_table_state class as well. close_performance_schema_table(): Got rid of duplicated code. sql/sql_class.cc: Instead of using separate MDL_context for opening system tables we now create MDL savepoint in the main context before opening such tables and rollback to this savepoint after closing them. To support this change methods of THD responsible for saving/restoring open table state were changed to use Open_tables_backup class which in addition to Open_table_state has a member for this savepoint. Also releasing metadata lock on system table is now responsibility of THD::restore_backup_open_tables_state(). Adjusted assert in THD::cleanup() to take into account fact that now we also use MDL sentinel for global read lock. sql/sql_class.h: Instead of using separate MDL_context for opening system tables we now create MDL savepoint in the main context before opening such tables and rollback to this savepoint after closing them. As result: - 'mdl_context' member was moved out of Open_tables_state to THD class. enter_locked_tables_mode()/leave_locked_tables_mode() had to follow. - Methods of THD responsible for saving/restoring open table state were changed to use Open_tables_backup class which in addition to Open_table_state has a member for this savepoint. Changed Open_table_context class to store MDL_request object for global intention exclusive lock acquired when opening tables. sql/sql_delete.cc: MDL subsystem no longer implicitly acquires global intention exclusive metadata lock when per-object exclusive metadata lock is acquired. Now this has to be done by explicit calls outside of MDL subsystem. sql/sql_help.cc: Instead of using separate MDL_context for opening system tables we now create MDL savepoint in the main context before opening such tables and rollback to this savepoint after closing them. To support this change methods of THD responsible for saving/restoring open table state were changed to use Open_tables_backup class which in addition to Open_table_state has a member for this savepoint. As result code opening/closing system tables was changed to use Open_tables_backup instead of Open_table_state class as well. sql/sql_parse.cc: Adjusted assert reload_acl_and_cache() to the fact that global read lock now takes full-blown metadata lock. sql/sql_plist.h: Added support for element counting to I_P_List list template. One can use policy classes to specify if such counting is needed or not needed for particular list. sql/sql_show.cc: Instead of using separate MDL_context for opening tables for I_S purposes we now create MDL savepoint in the main context before opening tables and rollback to this savepoint after closing them. To support this and similar change for system tables methods of THD responsible for saving/restoring open table state were changed to use Open_tables_backup class which in addition to Open_table_state has a member for this savepoint. As result code opening/closing tables for I_S purposes was changed to use Open_tables_backup instead of Open_table_state class as well. sql/sql_table.cc: mysql_rm_tables_part2(): Since now global intention exclusive metadata lock is ordinary metadata lock we no longer can rely that by releasing MDL locks on all tables we will release all locks acquired by this routine. So in non-LOCK-TABLES mode we have to release all locks acquired explicitly. prepare_for_repair(), mysql_alter_table(): MDL subsystem no longer implicitly acquires global intention exclusive metadata lock when per-object exclusive metadata lock is acquired. Now this has to be done by explicit calls outside of MDL subsystem. sql/tztime.cc: Instead of using separate MDL_context for opening system tables we now create MDL savepoint in the main context before opening such tables and rollback to this savepoint after closing them. To support this change methods of THD responsible for saving/restoring open table state were changed to use Open_tables_backup class which in addition to Open_table_state has a member for this savepoint. As result code opening/closing system tables was changed to use Open_tables_backup instead of Open_table_state class as well. Also changed code not to use special mechanism for open system tables when it is not really necessary. |
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Marc Alff
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e0e0f9e3d4 |
WL#2360 Performance schema
Part V: performance schema implementation |
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Marc Alff
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3d91522561 |
WL#2360 Performance schema
Part IV: sql instrumentation |
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Konstantin Osipov
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bf9c1b7353 |
Apply and review:
3655 Jon Olav Hauglid 2009-10-19 Bug #30977 Concurrent statement using stored function and DROP FUNCTION breaks SBR Bug #48246 assert in close_thread_table Implement a fix for: Bug #41804 purge stored procedure cache causes mysterious hang for many minutes Bug #49972 Crash in prepared statements The problem was that concurrent execution of DML statements that use stored functions and DDL statements that drop/modify the same function might result in incorrect binary log in statement (and mixed) mode and therefore break replication. This patch fixes the problem by introducing metadata locking for stored procedures and functions. This is similar to what is done in Bug#25144 for views. Procedures and functions now are locked using metadata locks until the transaction is either committed or rolled back. This prevents other statements from modifying the procedure/function while it is being executed. This provides commit ordering - guaranteeing serializability across multiple transactions and thus fixes the reported binlog problem. Note that we do not take locks for top-level CALLs. This means that procedures called directly are not protected from changes by simultaneous DDL operations so they are executed at the state they had at the time of the CALL. By not taking locks for top-level CALLs, we still allow transactions to be started inside procedures. This patch also changes stored procedure cache invalidation. Upon a change of cache version, we no longer invalidate the entire cache, but only those routines which we use, only when a statement is executed that uses them. This patch also changes the logic of prepared statement validation. A stored procedure used by a prepared statement is now validated only once a metadata lock has been acquired. A version mismatch causes a flush of the obsolete routine from the cache and statement reprepare. Incompatible changes: 1) ER_LOCK_DEADLOCK is reported for a transaction trying to access a procedure/function that is locked by a DDL operation in another connection. 2) Procedure/function DDL operations are now prohibited in LOCK TABLES mode as exclusive locks must be taken all at once and LOCK TABLES provides no way to specifiy procedures/functions to be locked. Test cases have been added to sp-lock.test and rpl_sp.test. Work on this bug has very much been a team effort and this patch includes and is based on contributions from Davi Arnaut, Dmitry Lenev, Magne Mæhre and Konstantin Osipov. mysql-test/r/ps_ddl.result: Update results (Bug#30977). mysql-test/r/ps_ddl1.result: Update results (Bug#30977). mysql-test/r/sp-error.result: Update results (Bug#30977). mysql-test/r/sp-lock.result: Update results (Bug#30977). mysql-test/suite/rpl/r/rpl_sp.result: Update results (Bug#30977). mysql-test/suite/rpl/t/rpl_sp.test: Add a test case for Bug#30977. mysql-test/t/ps_ddl.test: Update comments. We no longer re-prepare a prepared statement when a stored procedure used in top-level CALL is changed. mysql-test/t/ps_ddl1.test: Modifying stored procedure p1 no longer invalidates prepared statement "call p1" -- we can re-use the prepared statement without invalidation. mysql-test/t/sp-error.test: Use a constant for an error value. mysql-test/t/sp-lock.test: Add test coverage for Bug#30977. sql/lock.cc: Implement lock_routine_name() - a way to acquire an exclusive metadata lock (ex- name-lock) on stored procedure/function. sql/sp.cc: Change semantics of sp_cache_routine() -- now it has an option to make sure that the routine that is cached is up to date (has the latest sp cache version). Add sp_cache_invalidate() to sp_drop_routine(), where it was missing (a bug!). Acquire metadata locks for SP DDL (ALTER/CREATE/DROP). This is the core of the fix for Bug#30977. Since caching and cache invalidation scheme was changed, make sure we don't invalidate the SP cache in the middle of a stored routine execution. At the same time, make sure we don't access stale data due to lack of invalidation. For that, change ALTER FUNCTION/PROCEDURE to not use the cache, and SHOW PROCEDURE CODE/SHOW CREATE PROCEDURE/FUNCTION to always read an up to date version of the routine from the cache. sql/sp.h: Add a helper wrapper around sp_cache_routine(). sql/sp_cache.cc: Implement new sp_cache_version() and sp_cache_flush_obsolete(). Now we flush stale routines individually, rather than all at once. sql/sp_cache.h: Update signatures of sp_cache_version() and sp_cache_flush_obsolete(). sql/sp_head.cc: Add a default initialization of sp_head::m_sp_cache_version. Remove a redundant sp_head::create(). sql/sp_head.h: Add m_sp_cache_version to sp_head class - we now keep track of every routine in the stored procedure cache, rather than of the entire cache. sql/sql_base.cc: Implement prelocking for stored routines. Validate stored routines after they were locked. Flush obsolete routines upon next access, one by one, not all at once (Bug#41804). Style fixes. sql/sql_class.h: Rename a Open_table_context method. sql/sql_parse.cc: Make sure stored procedures DDL commits the active transaction (issues an implicit commit before and after). Remove sp_head::create(), a pure redundancy. Move the semantical check during alter routine inside sp_update_routine() code in order to: - avoid using SP cache during update, it may be obsolete. - speed up and simplify the update procedure. Remove sp_cache_flush_obsolete() calls, we no longer flush the entire cache, ever, stale routines are flushed before next use, one at a time. sql/sql_prepare.cc: Move routine metadata validation to open_and_process_routine(). Fix Bug#49972 (don't swap flags at reprepare). Reset Sroutine_hash_entries in reinit_stmt_before_use(). Remove SP cache invalidation, it's now done by open_tables(). sql/sql_show.cc: Fix a warning: remove an unused label. sql/sql_table.cc: Reset mdl_request.ticket for tickets acquired for routines inlined through a view, in CHECK TABLE statement, to satisfy an MDL assert. sql/sql_update.cc: Move the cleanup of "translation items" to close_tables_for_reopen(), since it's needed in all cases when we back off, not just the back-off in multi-update. This fixes a bug when the server would crash on attempt to back off when opening tables for a statement that uses information_schema tables. |
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Konstantin Osipov
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dfdbc84585 |
A prerequisite patch for the fix for Bug#46224
"HANDLER statements within a transaction might lead to deadlocks". Introduce a notion of a sentinel to MDL_context. A sentinel is a ticket that separates all tickets in the context into two groups: before and after it. Currently we can have (and need) only one designated sentinel -- it separates all locks taken by LOCK TABLE or HANDLER statement, which must survive COMMIT and ROLLBACK and all other locks, which must be released at COMMIT or ROLLBACK. The tricky part is maintaining the sentinel up to date when someone release its corresponding ticket. This can happen, e.g. if someone issues DROP TABLE under LOCK TABLES (generally, see all calls to release_all_locks_for_name()). MDL_context::release_ticket() is modified to take care of it. ****** A fix and a test case for Bug#46224 "HANDLER statements within a transaction might lead to deadlocks". An attempt to mix HANDLER SQL statements, which are transaction- agnostic, an open multi-statement transaction, and DDL against the involved tables (in a concurrent connection) could lead to a deadlock. The deadlock would occur when HANDLER OPEN or HANDLER READ would have to wait on a conflicting metadata lock. If the connection that issued HANDLER statement also had other metadata locks (say, acquired in scope of a transaction), a classical deadlock situation of mutual wait could occur. Incompatible change: entering LOCK TABLES mode automatically closes all open HANDLERs in the current connection. Incompatible change: previously an attempt to wait on a lock in a connection that has an open HANDLER statement could wait indefinitely/deadlock. After this patch, an error ER_LOCK_DEADLOCK is produced. The idea of the fix is to merge thd->handler_mdl_context with the main mdl_context of the connection, used for transactional locks. This makes deadlock detection possible, since all waits with locks are "visible" and available to analysis in a single MDL context of the connection. Since HANDLER locks and transactional locks have a different life cycle -- HANDLERs are explicitly open and closed, and so are HANDLER locks, explicitly acquired and released, whereas transactional locks "accumulate" till the end of a transaction and are released only with COMMIT, ROLLBACK and ROLLBACK TO SAVEPOINT, a concept of "sentinel" was introduced to MDL_context. All locks, HANDLER and others, reside in the same linked list. However, a selected element of the list separates locks with different life cycle. HANDLER locks always reside at the end of the list, after the sentinel. Transactional locks are prepended to the beginning of the list, before the sentinel. Thus, ROLLBACK, COMMIT or ROLLBACK TO SAVEPOINT, only release those locks that reside before the sentinel. HANDLER locks must be released explicitly as part of HANDLER CLOSE statement, or an implicit close. The same approach with sentinel is also employed for LOCK TABLES locks. Since HANDLER and LOCK TABLES statement has never worked together, the implementation is made simple and only maintains one sentinel, which is used either for HANDLER locks, or for LOCK TABLES locks. mysql-test/include/handler.inc: Add test coverage for Bug#46224 "HANDLER statements within a transaction might lead to deadlocks". Extended HANDLER coverage to cover a mix of HANDLER, transactions and DDL statements. mysql-test/r/handler_innodb.result: Update results (Bug#46224). mysql-test/r/handler_myisam.result: Update results (Bug#46224). sql/lock.cc: Remove thd->some_tables_deleted, it's never used. sql/log_event.cc: No need to check for thd->locked_tables_mode, it's done inside release_transactional_locks(). sql/mdl.cc: Implement the concept of HANDLER and LOCK TABLES "sentinel". Implement a method to clone an acquired ticket. Do not return tickets beyond the sentinel when acquiring locks, create a copy. Remove methods to merge and backup MDL_context, they are now not used (Hurra!). This opens a path to a proper constructor and destructor of class MDL_context (to be done in a separate patch). Modify find_ticket() to provide information about where the ticket position is with regard to the sentinel. sql/mdl.h: Add declarations necessary for the implementation of the concept of "sentinel", a dedicated ticket separating transactional and non-transactional locks. sql/mysql_priv.h: Add mark_tmp_table_for_reuse() declaration, a function to "close" a single session (temporary) table. sql/sql_base.cc: Remove thd->some_tables_deleted. Modify deadlock-prevention asserts and deadlock detection heuristics to take into account that from now on HANDLER locks reside in the same locking context. Add broadcast_refresh() to mysql_notify_thread_having_shared_lock(): this is necessary for the case when a thread having a shared lock is asleep in tdc_wait_for_old_versions(). This situation is only possible with HANDLER t1 OPEN; FLUSH TABLE (since all over code paths that lead to tdc_wait_for_old_versions() always have an empty MDL_context). Previously the server would simply deadlock in this situation. sql/sql_class.cc: Remove now unused member "THD::some_tables_deleted". Move mysql_ha_cleanup() a few lines above in THD::cleanup() to make sure that all handlers are closed when it's time to destroy the MDL_context of this connection. Remove handler_mdl_context and handler_tables. sql/sql_class.h: Remove THD::handler_tables, THD::handler_mdl_context, THD::some_tables_deleted. sql/sql_handler.cc: Remove thd->handler_tables. Remove thd->handler_mdl_context. Rewrite mysql_ha_open() to have no special provision for MERGE tables, now that we don't have to manipulate with thd->handler_tables it's easy to do. Remove dead code. Fix a bug in mysql_ha_flush() when we would always flush a temporary HANDLER when mysql_ha_flush() is called (actually mysql_ha_flush() never needs to flush temporary tables). sql/sql_insert.cc: Update a comment, no more thd->some_tables_deleted. sql/sql_parse.cc: Implement an incompatible change: entering LOCK TABLES closes active HANDLERs, if any. Now that we have a sentinel, we don't need to check for thd->locked_tables_mode when releasing metadata locks in COMMIT/ROLLBACK. sql/sql_plist.h: Add new (now necessary) methods to the list class. sql/sql_prepare.cc: Make sure we don't release HANDLER locks when rollback to a savepoint, set to not keep locks taken at PREPARE. sql/sql_servers.cc: Update to a new signature of MDL_context::release_all_locks(). sql/sql_table.cc: Remove thd->some_tables_deleted. sql/transaction.cc: Add comments. Make sure rollback to (MDL) savepoint works under LOCK TABLES and with HANDLER tables. |
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Marc Alff
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0531f85e16 | Merge cleanup | ||
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Konstantin Osipov
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b89c882c5d | Merge with next-4284. | ||
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Jon Olav Hauglid
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3d062adf25 |
Backport of revno: 3685
Bug #48210 FLUSH TABLES WITH READ LOCK deadlocks against concurrent CREATE PROCEDURE This deadlock occured between a) CREATE PROCEDURE (or other commands listed below) b) FLUSH TABLES WITH READ LOCK If the execution of them happened in the following order: - a) opens a table (e.g. mysql.proc) - b) locks the global read lock (or GRL) - a) sleeps inside wait_if_global_read_lock() - b) increases refresh_version and sleeps waiting for old tables to go away Note that a) must start waiting on the GRL before FLUSH increases refresh_version. Otherwise a) won't wait on the GRL and instead close its tables for reopen, allowing FLUSH to complete and thus avoid the deadlock. With this patch the deadlock is avoided by making CREATE PROCEDURE acquire a protection against global read locks before it starts executing. This means that FLUSH TABLES WITH READ LOCK will have to wait until CREATE PROCEDURE completes before acquiring the global read lock, thereby avoiding the deadlock. This is implemented by introducing a new SQL command flag called CF_PROTECT_AGAINST_GRL. Commands marked with this flag will acquire a GRL protection in the beginning of mysql_execute_command(). This patch adds the flag to CREATE, ALTER and DROP for PROCEDURE and FUNCTION, as well as CREATE USER, DROP USER, RENAME USER and REVOKE ALL. All these commands either call open_grant_tables() or open_system_table_for_updated() which make them susceptible for this deadlock. The patch also adds the CF_PROTECT_AGAINST_GRL flag to a number of commands that previously acquired GRL protection in their respective SQLCOM case in mysql_execute_command(). Test case that checks for GRL protection for CREATE PROCEDURE and CREATE USER added to mdl_sync.test. |
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Konstantin Osipov
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f805517522 |
Backport a part of Monty's fix for Bug#39396, rev. 2736.2.11
"ha_maria.cc:2415: assertion in ha_maria::store_lock()". sql/lock.cc: Fixed wrong cleanup of mysql_lock_tables() - We must call read_lock_data() BEFORE we set lock_count to 0. Added DBUG statements. |
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Konstantin Osipov
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f129367288 | Merge with next-4284. | ||
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Konstantin Osipov
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f26f632b44 |
Backport of:
------------------------------------------------------------ revno: 2617.68.25 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-next-bg-pre2-2 timestamp: Wed 2009-09-16 18:26:50 +0400 message: Follow-up for one of pre-requisite patches for fixing bug #30977 "Concurrent statement using stored function and DROP FUNCTION breaks SBR". Made enum_mdl_namespace enum part of MDL_key class and removed MDL_ prefix from the names of enum members. In order to do the latter changed name of PROCEDURE symbol to PROCEDURE_SYM (otherwise macro which was automatically generated for this symbol conflicted with MDL_key::PROCEDURE enum member). |
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Marc Alff
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c082955f06 |
WL#2360 Performance schema
Part III: mysys instrumentation |
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Jon Olav Hauglid
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f3e9b392ac |
Backport of revno: 2617.68.13
Introduce a counter for protection against global read lock on thread level. The functions for protection against global read lock sometimes need a local variable to signal when the protection is set, and hence need to be released. It would be better to control this behaviour via a counter on the THD struct, telling how many times the protection has been claimed by the current thread. A side-effect of the fix is that if protection is claimed twice for a thread, only a simple increment is required for the second claim, instead of a mutex-protected increment of the global variable protect_against_global_read_lock. sql/lock.cc: Count how many times that we have claimed protection against global read lock. Assert that we really have the protection when releasing it. Added comments to all functions operating on global_read_lock. sql/sql_class.cc: Added the counter variable global_read_lock_protection. sql/sql_class.h: Added the counter variable global_read_lock_protection. sql/sql_parse.cc: Replaced test on local variable need_start_waiting with test on thd->global_read_lock_protection. sql/sql_table.cc: Replaced test on local variable need_start_waiting with test on thd->global_read_lock_protection. sql/sql_trigger.cc: Inserted test on thd->global_read_lock_protection. |
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Jon Olav Hauglid
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546e16ebd8 |
Backport of revno: 2617.69.40
A pre-requisite patch for Bug#30977 "Concurrent statement using stored function and DROP FUNCTION breaks SBR". This patch changes the MDL API by introducing a namespace for lock keys: MDL_TABLE for tables and views and MDL_PROCEDURE for stored procedures and functions. The latter is needed for the fix for Bug#30977. |
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Konstantin Osipov
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ce5c87a3d3 |
Backport of:
---------------------------------------------------------- revno: 2617.69.20 committer: Konstantin Osipov <kostja@sun.com> branch nick: 5.4-4284-1-assert timestamp: Thu 2009-08-13 18:29:55 +0400 message: WL#4284 "Transactional DDL locking" A review fix. Since WL#4284 implementation separated MDL_request and MDL_ticket, MDL_request becamse a utility object necessary only to get a ticket. Store it by-value in TABLE_LIST with the intent to merge MDL_request::key with table_list->table_name and table_list->db in future. Change the MDL subsystem to not require MDL_requests to stay around till close_thread_tables(). Remove the list of requests from the MDL context. Requests for shared metadata locks acquired in open_tables() are only used as a list in recover_from_failed_open_table_attempt(), which calls mdl_context.wait_for_locks() for this list. To keep such list for recover_from_failed_open_table_attempt(), introduce a context class (Open_table_context), that collects all requests. A lot of minor cleanups and simplications that became possible with this change. sql/event_db_repository.cc: Remove alloc_mdl_requests(). Now MDL_request instance is a member of TABLE_LIST, and init_one_table() initializes it. sql/ha_ndbcluster_binlog.cc: Remove now unnecessary declaration and initialization of binlog_mdl_request. sql/lock.cc: No need to allocate MDL requests in lock_table_names() now. sql/log.cc: Use init_one_table() method, remove alloc_mdl_requests(), which is now unnecessary. sql/log_event.cc: No need to allocate mdl_request separately now. Use init_one_table() method. sql/log_event_old.cc: Update to the new signature of close_tables_for_reopen(). sql/mdl.cc: Update try_acquire_exclusive_lock() to be more easy to use. Function lock_table_name_if_not_cached() has been removed. Make acquire_shared_lock() signature consistent with try_acquire_exclusive_lock() signature. Remove methods that are no longer used. Update comments. sql/mdl.h: Implement an assignment operator that doesn't copy MDL_key (MDL_key::operator= is private and should remain private). This is a hack to work-around assignment of TABLE_LIST by value in several places. Such assignments violate encapsulation, since only perform a shallow copy. In most cases these assignments are a hack on their own. sql/mysql_priv.h: Update signatures of close_thread_tables() and close_tables_for_reopen(). sql/sp.cc: Allocate TABLE_LIST in thd->mem_root. Use init_one_table(). sql/sp_head.cc: Use init_one_table(). Remove thd->locked_tables_root, it's no longer needed. sql/sql_acl.cc: Use init_mdl_requests() and init_one_table(). sql/sql_base.cc: Update to new signatures of try_acquire_shared_lock() and try_acquire_exclusive_lock(). Remove lock_table_name_if_not_cached(). Fix a bug in open_ltable() that would not return ER_LOCK_DEADLOCK in case of a failed lock_tables() and a multi-statement transaction. Fix a bug in open_and_lock_tables_derived() that would not return ER_LOCK_DEADLOCK in case of a multi-statement transaction and a failure of lock_tables(). Move assignment of enum_open_table_action to a method of Open_table_context, a new class that maintains information for backoff actions. Minor rearrangements of the code. Remove alloc_mdl_requests() in functions that work with system tables: instead the patch ensures that callers always initialize TABLE_LIST argument. sql/sql_class.cc: THD::locked_tables_root is no more. sql/sql_class.h: THD::locked_tables_root is no more. Add a declaration for Open_table_context class. sql/sql_delete.cc: Update to use the simplified MDL API. sql/sql_handler.cc: TABLE_LIST::mdl_request is stored by-value now. Ensure that mdl_request.ticket is NULL for every request that is passed into MDL, to satisfy MDL asserts. @ sql/sql_help.cc Function open_system_tables_for_read() no longer initializes mdl_requests. Move TABLE_LIST::mdl_request initialization closer to TABLE_LIST initialization. sql/sql_help.cc: Function open_system_tables_for_read() no longer initializes mdl_requests. Move TABLE_LIST::mdl_request initialization closer to TABLE_LIST initialization. sql/sql_insert.cc: Remove assignment by-value of TABLE_LIST in TABLEOP_HOOKS. We can't carry over a granted MDL ticket from one table list to another. sql/sql_parse.cc: Change alloc_mdl_requests() -> init_mdl_requests(). @todo We can remove init_mdl_requests() altogether in some places: all places that call add_table_to_list() already have mdl requests initialized. sql/sql_plugin.cc: Use init_one_table(). THD::locked_tables_root is no more. sql/sql_servers.cc: Use init_one_table(). sql/sql_show.cc: Update acquire_high_priority_shared_lock() to use TABLE_LIST::mdl_request rather than allocate an own. Fix get_trigger_table_impl() to use init_one_table(), check for out of memory, follow the coding style. sql/sql_table.cc: Update to work with TABLE_LIST::mdl_request by-value. Remove lock_table_name_if_not_cached(). The code that used to delegate to it is quite simple and concise without it now. sql/sql_udf.cc: Use init_one_table(). sql/sql_update.cc: Update to use the new signature of close_tables_for_reopen(). sql/table.cc: Move re-setting of mdl_requests for prepared statements and stored procedures from close_thread_tables() to reinit_stmt_before_use(). Change alloc_mdl_requests() to init_mdl_requests(). init_mdl_requests() is a hack that can't be deleted until we don't have a list-aware TABLE_LIST constructor. Hopefully its use will be minimal sql/table.h: Change alloc_mdl_requests() to init_mdl_requests() TABLE_LIST::mdl_request is stored by value. sql/tztime.cc: We no longer initialize mdl requests in open_system_tables_for*() functions. Move this initialization closer to initialization of the rest of TABLE_LIST members. storage/myisammrg/ha_myisammrg.cc: Simplify mdl_request initialization. |
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Konstantin Osipov
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a9013f8fba |
Backport of:
---------------------------------------------------------- revno: 2617.23.20 committer: Konstantin Osipov <kostja@sun.com> branch nick: mysql-6.0-runtime timestamp: Wed 2009-03-04 16:31:31 +0300 message: WL#4284 "Transactional DDL locking" Review comments: "Objectify" the MDL API. MDL_request and MDL_context still need manual construction and destruction, since they are used in environment that is averse to constructors/destructors. sql/mdl.cc: Improve comments. Add asserts to backup()/restore_from_backup()/merge() methods. Fix an order bug in the error path of mdl_acquire_exclusive_locks(): we used to first free a ticket object, and only then exclude it from the list of tickets. |
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Konstantin Osipov
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f477e66ec5 |
Backport of:
------------------------------------------------------------ revno: 2617.23.18 committer: Davi Arnaut <Davi.Arnaut@Sun.COM> branch nick: 4284-6.0 timestamp: Mon 2009-03-02 18:18:26 -0300 message: Bug#989: If DROP TABLE while there's an active transaction, wrong binlog order WL#4284: Transactional DDL locking This is a prerequisite patch: These changes are intended to split lock requests from granted locks and to allow the memory and lifetime of granted locks to be managed within the MDL subsystem. Furthermore, tickets can now be shared and therefore are used to satisfy multiple lock requests, but only shared locks can be recursive. The problem is that the MDL subsystem morphs lock requests into granted locks locks but does not manage the memory and lifetime of lock requests, and hence, does not manage the memory of granted locks either. This can be problematic because it puts the burden of tracking references on the users of the subsystem and it can't be easily done in transactional contexts where the locks have to be kept around for the duration of a transaction. Another issue is that recursive locks (when the context trying to acquire a lock already holds a lock on the same object) requires that each time the lock is granted, a unique lock request/granted lock structure structure must be kept around until the lock is released. This can lead to memory leaks in transactional contexts as locks taken during the transaction should only be released at the end of the transaction. This also leads to unnecessary wake ups (broadcasts) in the MDL subsystem if the context still holds a equivalent of the lock being released. These issues are exacerbated due to the fact that WL#4284 low-level design says that the implementation should "2) Store metadata locks in transaction memory root, rather than statement memory root" but this is not possible because a memory root, as implemented in mysys, requires all objects allocated from it to be freed all at once. This patch combines review input and significant code contributions from Konstantin Osipov (kostja) and Dmitri Lenev (dlenev). mysql-test/r/mdl_sync.result: Add test case result. mysql-test/t/mdl_sync.test: Add test case for shared lock upgrade case. sql/event_db_repository.cc: Rename mdl_alloc_lock to mdl_request_alloc. sql/ha_ndbcluster_binlog.cc: Use new function names to initialize MDL lock requests. sql/lock.cc: Rename MDL functions. sql/log_event.cc: The MDL request now holds the table and database name data (MDL_KEY). sql/mdl.cc: Move the MDL key to the MDL_LOCK structure in order to make the object suitable for allocation from a fixed-size allocator. This allows the simplification of the lists in the MDL_LOCK object, which now are just two, one for granted tickets and other for waiting (upgraders) tickets. Recursive requests for a shared lock on the same object can now be granted using the same lock ticket. This schema is only used for shared locks because that the only case that matters. This is used to avoid waste of resources in case a context (connection) already holds a shared lock on a object. sql/mdl.h: Introduce a metadata lock object key which is used to uniquely identify lock objects. Separate the structure used to represent pending lock requests from the structure used to represent granted metadata locks. Rename functions used to manipulate locks requests in order to have a more consistent function naming schema. sql/sp_head.cc: Rename mdl_alloc_lock to mdl_request_alloc. sql/sql_acl.cc: Rename alloc_mdl_locks to alloc_mdl_requests. sql/sql_base.cc: Various changes to accommodate that lock requests are separated from lock tickets (granted locks). sql/sql_class.h: Last acquired lock before the savepoint was set. sql/sql_delete.cc: Various changes to accommodate that lock requests are separated from lock tickets (granted locks). sql/sql_handler.cc: Various changes to accommodate that lock requests are separated from lock tickets (granted locks). sql/sql_insert.cc: Rename alloc_mdl_locks to alloc_mdl_requests. sql/sql_parse.cc: Rename alloc_mdl_locks to alloc_mdl_requests. sql/sql_plist.h: Typedef for iterator type. sql/sql_plugin.cc: Rename alloc_mdl_locks to alloc_mdl_requests. sql/sql_servers.cc: Rename alloc_mdl_locks to alloc_mdl_requests. sql/sql_show.cc: Various changes to accommodate that lock requests are separated from lock tickets (granted locks). sql/sql_table.cc: Various changes to accommodate that lock requests are separated from lock tickets (granted locks). sql/sql_trigger.cc: Save reference to the lock ticket so it can be downgraded later. sql/sql_udf.cc: Rename alloc_mdl_locks to alloc_mdl_requests. sql/table.cc: Rename mdl_alloc_lock to mdl_request_alloc. sql/table.h: Separate MDL lock requests from lock tickets (granted locks). storage/myisammrg/ha_myisammrg.cc: Rename alloc_mdl_locks to alloc_mdl_requests. |
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Konstantin Osipov
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cd155be564 |
Backport of:
------------------------------------------------------------ revno: 3035.4.1 committer: Davi Arnaut <Davi.Arnaut@Sun.COM> branch nick: 39897-6.0 timestamp: Thu 2009-01-15 12:17:57 -0200 message: Bug#39897: lock_multi fails in pushbuild: timeout waiting for processlist The problem is that relying on the "Table lock" thread state in its current position to detect that a thread is waiting on a lock is race prone. The "Table lock" state change happens before the thread actually tries to grab a lock on a table. The solution is to move the "Table lock" state so that its set only when a thread is actually going to wait for a lock. The state change happens after the thread fails to grab the lock (because it is owned by other thread) and proceeds to wait on a condition. This is considered part of work related to WL#4284 "Transactional DDL locking" Warning: this patch contains an incompatible change. When waiting on a lock in thr_lock.c, the server used to display "Locked" processlist state. After this patch, the state is "Table lock". The new state was actually intended to be display since year 2002, when Monty added it. But up until removal of thd->locked boolean member, this state was ignored by SHOW PROCESSLIST code. mysql-test/r/lock_multi.result: A style fix. mysql-test/r/sp-threads.result: Changed output of SHOW PROCESSLIST (new wait state). mysql-test/t/lock_multi.test: Use a more accurate state description when waiting inside thr_lock.c. mysql-test/t/lock_sync.test: Use a more accurate state description when waiting inside thr_lock.c. mysql-test/t/multi_update.test: Use a more accurate state description when waiting inside thr_lock.c. mysql-test/t/query_cache_28249.test: Use a more accurate state description when waiting inside thr_lock.c. mysql-test/t/sp_notembedded.test: Use a more accurate state description when waiting inside thr_lock.c. mysql-test/t/status.test: Use a more accurate state description when waiting inside thr_lock.c. mysys/thr_lock.c: Update thread state while waiting for a table lock. sql/lock.cc: State change was moved inside thr_lock.c. |
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Konstantin Osipov
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77cbfd85ee |
Backport of:
---------------------------------------------------------- revno: 2630.4.35 committer: Konstantin Osipov <konstantin@mysql.com> branch nick: mysql-6.0-3726 timestamp: Wed 2008-06-25 16:44:00 +0400 message: Fix a MyISAM-specific bug in the new implementation of LOCK TABLES (WL#3726). If more than one instance of a MyISAM table are open in the same connection, all of them must share the same status_param. Otherwise, unlock of a table may lead to lost records. See also comments in thr_lock.c. include/thr_lock.h: Declare thr_lock_merge_status(). mysql-test/r/lock.result: Update test results (WL#3726). mysql-test/t/lock.test: Add a test case for the situation when the same table is locked twice by LOCK TABLES, and only one instance is updated. mysys/thr_lock.c: Move the code that makes sure all status_params of the same table are shared into a separate function. sql/lock.cc: Make sure that status_param is shared when a table is reopened. |
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Konstantin Osipov
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e3b3907c4f |
Backport of:
------------------------------------------------------------ revno: 2630.4.32 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w2 timestamp: Thu 2008-06-19 16:39:58 +0400 message: WL#3726 "DDL locking for all metadata objects". After-review fixes in progress. Ensure that metadata locking subsystem properly handles out-of-memory conditions. Clarified MDL interface by separating release of locks and removal of lock requests from the context. sql/lock.cc: mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and mdl_remove_lock() to do this. sql/mdl.cc: Ensured that metadata locking subsystem properly handles out-of-memory conditions. Introduced new MDL_INITIALIZED state for metadata lock request which is used in all cases when lock is not acquired and we have not associated request with object respesenting lock. MDL_PENDING is now only used for requests for exclusive locks which are added to the MDL_LOCK::waiting_exclusive queue. mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and newly introduced mdl_remove_lock() to do this. Also renamed mdl_release_all_locks_for_name() to emphasize that it also actually removes lock requests from the context. Finally mdl_try_acquire_exclusive_lock() is now returs information about encountered lock conflict in separate out parameter since its return value is used for distinguishing between error (e.g. due to OOM) and success. sql/mdl.h: Introduced new MDL_INITIALIZED state for metadata lock request which is used in all cases when lock is not acquired and we have not associated request with object respesenting lock. MDL_PENDING is now only used for requests for exclusive locks which are added to the MDL_LOCK::waiting_exclusive queue. mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and newly introduced mdl_remove_lock() to do this. Also renamed mdl_release_all_locks_for_name() to emphasize that it also actually removes lock requests from the context. Finally mdl_try_acquire_exclusive_lock() is now returs information about encountered lock conflict in separate out parameter since its return value is used for distinguishing between error (e.g. due to OOM) and success. sql/sql_base.cc: mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and mdl_remove_lock() to do this. Also adjusted open_table() to ensure that it releases/removes metadata locks in case of error after adding/acquiring them (unless keeping these lock requests is required for recovering action). sql/sql_delete.cc: mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and mdl_remove_lock() to do this. sql/sql_handler.cc: mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and mdl_remove_lock() to do this. sql/sql_show.cc: mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and mdl_remove_lock() to do this. sql/sql_table.cc: Renamed mdl_release_all_locks_for_name() to emphasize that it also actually removes lock requests from the context. mdl_release_lock(), mdl_acquire_exclusive_locks() and mdl_try_acquire_exclusive_lock() are no longer responsible for removal of metadata lock requests from the context. One should explicitly call mdl_remove_all_locks() and mdl_remove_lock() to do this. Finally mdl_try_acquire_exclusive_lock() is now returs information about encountered lock conflict in separate out parameter since its return value is used for distinguishing between error (e.g. due to OOM) and success. |
||
|
Konstantin Osipov
|
3104af49cd |
Backport of:
---------------------------------------------------------- revno: 2630.10.1 committer: Konstantin Osipov <konstantin@mysql.com> branch nick: mysql-6.0-lock-tables-tidyup timestamp: Wed 2008-06-11 15:49:58 +0400 message: WL#3726, review fixes. Now that we have metadata locks, we don't need to keep a crippled TABLE instance in the table cache to indicate that a table is locked. Remove all code that used this technique. Instead, rely on metadata locks and use the standard open_table() and close_thread_table() to manipulate with the table cache tables. Removes a list of functions that have become unused (see the comment for sql_base.cc for details). Under LOCK TABLES, keep a TABLE_LIST instance for each table that may be temporarily closed. For that, implement an own class for LOCK TABLES mode, Locked_tables_list. This is a pre-requisite patch for WL#4144. This is not exactly a backport: there is no new online ALTER table in Celosia, so the old alter table code was changed to work with the new table cache API. mysql-test/r/lock.result: Update results (WL#3726 post-review patch). mysql-test/r/trigger-compat.result: We take the table from the table cache now, thus no warning. mysql-test/suite/rpl/r/rpl_trigger.result: We take the table from the table cache now, thus no warning. mysql-test/t/lock.test: Additional tests for LOCK TABLES mode (previously not covered by the test suite (WL#3726). sql/field.h: Remove reopen_table(). sql/lock.cc: Remove an obsolete parameter of mysql_lock_remove(). It's not used anywhere now either. sql/mysql_priv.h: Add 4 new open_table() flags. Remove declarations of removed functions. sql/sp_head.cc: Rename thd->mdl_el_root to thd->locked_tables_root. sql/sql_acl.cc: Use the new implementation of unlock_locked_tables(). sql/sql_base.cc: Implement class Locked_tables_list. Implement close_all_tables_for_name(). Rewrite close_cached_tables() to use the new reopen_tables(). Remove reopen_table(), reopen_tables(), reopen_table_entry() (ex. open_unireg_entry()), close_data_files_and_leave_as_placeholders(), close_handle_and_leave_table_as_placeholder(), close_cached_table(), table_def_change_share(), reattach_merge(), reopen_name_locked_table(), unlink_open_table(). Move acquisition of a metadata lock into an own function - open_table_get_mdl_lock(). sql/sql_class.cc: Deploy class Locked_tables_list. sql/sql_class.h: Declare class Locked_tables_list. Keep one instance of this class in class THD. Rename mdl_el_root to locked_tables_root. sql/sql_db.cc: Update a comment. sql/sql_insert.cc: Use the plain open_table() to open a just created table in CREATE TABLE .. SELECT. sql/sql_parse.cc: Use thd->locked_tables_list to enter and leave LTM_LOCK_TABLES mode. sql/sql_partition.cc: Deploy the new method of working with partitioned table locks. sql/sql_servers.cc: Update to the new signature of unlock_locked_tables(). sql/sql_table.cc: In mysql_rm_table_part2(), the branch that removes a table under LOCK TABLES, make sure that the table being dropped is also removed from THD::locked_tables_list. Update ALTER TABLE and CREATE TABLE LIKE implementation to use open_table() and close_all_tables_for_name() instead of reopen_tables(). sql/sql_trigger.cc: Use the new locking way. sql/table.h: Add TABLE::pos_in_locked_tables, which is used only under LOCK TABLES. |
||
|
Konstantin Osipov
|
5969dcda21 |
Backport of:
---------------------------------------------------------- revno: 2630.4.26 committer: Konstantin Osipov <konstantin@mysql.com> branch nick: mysql-6.0-prelocked_mode-to-push timestamp: Fri 2008-06-06 23:19:04 +0400 message: WL#3726: work on review comments. Remove thd->locked_tables. Always store MYSQL_LOCK instances in thd->lock. Rename thd->prelocked_mode to thd->locked_tables_mode. Use thd->locked_tables_mode to determine if we are under LOCK TABLES. Update the code to not assume that if thd->lock is set, LOCK TABLES mode is off. Review comments. sql/ha_ndbcluster_binlog.cc: Don't unlock the lock under LOCK TABLES (safety). sql/handler.cc: There is no thd->locked_tables any more. Update comments. sql/lock.cc: There is no thd->locked_tables any more. sql/log.cc: Rename thd->prelocked_mode to thd->locked_tables_mode. sql/set_var.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sp_head.cc: Rename thd->prelocked_mode to thd->locked_tables_mode. sql/sql_base.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. Remove thd->locked_tables. sql/sql_cache.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_class.cc: Avoid code duplication. Do not release the table locks prematurely if we're under LOCK TABLES. Use thd->locked_tables_mode instead of thd->locked_tables. sql/sql_class.h: Remove thd->locked_tables. Make prelocked mode a kind of LOCK TABLES mode. Update comments. sql/sql_cursor.cc: Update comments. sql/sql_insert.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. Rename thd->prelocked_mode to thd->locked_tables_mode. sql/sql_load.cc: Rename thd->prelocked_mode to thd->locked_tables_mode. sql/sql_parse.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. Remove thd->locked_tables. sql/sql_partition.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_rename.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_select.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_table.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_trigger.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_update.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. sql/sql_view.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. storage/myisam/ha_myisam.cc: Use thd->locked_tables_mode to determine if we are under LOCK TABLES. |
||
|
Konstantin Osipov
|
b05303c132 |
Backport of:
------------------------------------------------------------
revno: 2630.4.18
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Tue 2008-06-03 21:07:58 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After review fixes in progress.
Now during upgrading/downgrading metadata locks we deal with
individual metadata lock requests rather than with all requests
for this object in the context. This makes API a bit more clear
and makes adjust_mdl_locks_upgradability() much nicer.
sql/lock.cc:
lock_table_names():
Set TABLE_LIST::mdl_lock_data when allocating new metadata
lock request object for table list element.
sql/mdl.cc:
Now during upgrading/downgrading metadata locks we deal with
individual metadata lock requests rather than with all
requests for this object in the context. Adjusted upgrade/
downgrade functions accordingly.
We also got rid of mdl_release_exclusive_locks() and
now release locks individually. To simplify this process
mdl_release_all_locks_for_name() was introduced.
sql/mdl.h:
Now during upgrading/downgrading metadata locks we deal with
individual metadata lock requests rather than with all
requests for this object in the context. Adjusted upgrade/
downgrade functions accordingly.
We also got rid of mdl_release_exclusive_locks() and
now release locks individually. To simplify this process
mdl_release_all_locks_for_name() was introduced.
sql/sql_base.cc:
Now during upgrading/downgrading metadata locks we deal with
individual metadata lock requests rather than with all
requests for this object in the context.
We also got rid of mdl_release_exclusive_locks() and
now release locks individually.
sql/sql_parse.cc:
adjust_mdl_locks_upgradability() is much simplier now due to the
fact that now during upgrading/downgrading metadata locks we
deal with individual metadata lock requests rather than with
all requests for this object in the context.
sql/sql_table.cc:
Now during upgrading/downgrading metadata locks we deal with
individual metadata lock requests rather than with all
requests for this object in the context. Adjusted upgrade/
downgrade functions accordingly.
We also got rid of mdl_release_exclusive_locks() and
now release locks individually. To simplify this process
mdl_release_all_locks_for_name() was introduced.
sql/sql_trigger.cc:
ow during upgrading/downgrading metadata locks we deal with
individual metadata lock requests rather than with all
requests for this object in the context.
|
||
|
Konstantin Osipov
|
e23046d1bc |
Backport of:
------------------------------------------------------------ revno: 2630.4.17 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w2 timestamp: Thu 2008-05-29 16:52:56 +0400 message: WL#3726 "DDL locking for all metadata objects". After review fixes in progress. "The great correction of names". Renamed MDL_LOCK and MDL_LOCK_DATA classes to make usage of these names in metadata locking subsystem consistent with other parts of server (i.e. thr_lock.cc). Now we MDL_LOCK_DATA corresponds to request for a lock and MDL_LOCK to the lock itself. Adjusted code in MDL subsystem and other places using these classes accordingly. Did similar thing for GLOBAL_MDL_LOCK_DATA class and also changed name of its members to correspond to names of MDL_LOCK_DATA members. Finally got rid of usage of one letter variables in MDL code since it makes code harder to search in (according to reviewer). |
||
|
Konstantin Osipov
|
aeebede195 |
Backport of:
------------------------------------------------------------ revno: 2630.4.11 committer: Dmitry Lenev <dlenev@mysql.com> branch nick: mysql-6.0-3726-w timestamp: Tue 2008-05-27 21:31:53 +0400 message: WL#3726 "DDL locking for all metadata objects". After review fixes in progress. Changed mysql_lock_tables() to be no longer responsible for reopening table if waiting for the lock on it was aborted. This allows to get rid of several annoying functions. sql/ha_ndbcluster_binlog.cc: lock_tables() now also accepts set of options to be passed to mysql_lock_tables(). sql/lock.cc: Changed mysql_lock_tables() always requests caller to reopen table instead doing this on its own when waiting for lock was aborted. This allows us to get rid of several functions which were used in rare cases and significantly complicated our life. sql/log_event_old.cc: lock_tables() now also accepts set of options to be passed to mysql_lock_tables(). sql/mysql_priv.h: Now mysql_lock_tables() always requests caller to reopen table instead doing this on its own when waiting for lock was aborted. So we no longer need wait_for_tables() and table_is_used() functions and MYSQL_LOCK_NOTIFY_IF_NEED_REOPEN flag. open_and_lock_table_derived() and lock_tables() now accept options to be passed to open_tables() and mysql_lock_tables() calls. sql/sql_base.cc: Since now mysql_lock_tables() always requests caller to reopen table instead doing this on its own when waiting for lock was aborted we no longer need wait_for_tables(), table_is_used() and close_old_data_files() functions. open_and_lock_table_derived() and lock_tables() now accept options to be passed to open_tables() and mysql_lock_tables() calls. This was needed in order to get rid of redundant code in open_system_tables_for_read() function. sql/sql_handler.cc: mysql_lock_tables() is now always requests reopen if waiting for lock is aborted. MYSQL_LOCK_NOTIFY_IF_NEED_REOPEN flag was removed. sql/sql_insert.cc: handle_delayed_insert(): Since mysql_lock_tables() is no longer responsible for reopening tables when waiting for lock was aborted we have to handle such situation outside of this function. To simplify this extracted code opening table for delayed insert thread to separate method of Delayed_insert class. sql/sql_update.cc: lock_tables() now also accepts set of options to be passed to mysql_lock_tables(). |
||
|
Konstantin Osipov
|
eff3780dd8 |
Initial import of WL#3726 "DDL locking for all metadata objects".
Backport of:
------------------------------------------------------------
revno: 2630.4.1
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Fri 2008-05-23 17:54:03 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After review fixes in progress.
------------------------------------------------------------
This is the first patch in series. It transforms the metadata
locking subsystem to use a dedicated module (mdl.h,cc). No
significant changes in the locking protocol.
The import passes the test suite with the exception of
deprecated/removed 6.0 features, and MERGE tables. The latter
are subject to a fix by WL#4144.
Unfortunately, the original changeset comments got lost in a merge,
thus this import has its own (largely insufficient) comments.
This patch fixes Bug#25144 "replication / binlog with view breaks".
Warning: this patch introduces an incompatible change:
Under LOCK TABLES, it's no longer possible to FLUSH a table that
was not locked for WRITE.
Under LOCK TABLES, it's no longer possible to DROP a table or
VIEW that was not locked for WRITE.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.2
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:03:45 +0400
message:
WL#3726 "DDL locking for all metadata objects".
After review fixes in progress.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:08:51 +0400
message:
WL#3726 "DDL locking for all metadata objects"
Fixed failing Windows builds by adding mdl.cc to the lists
of files needed to build server/libmysqld on Windows.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.4
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 21:57:58 +0400
message:
WL#3726 "DDL locking for all metadata objects".
Fix for assert failures in kill.test which occured when one
tried to kill ALTER TABLE statement on merge table while it
was waiting in wait_while_table_is_used() for other connections
to close this table.
These assert failures stemmed from the fact that cleanup code
in this case assumed that temporary table representing new
version of table was open with adding to THD::temporary_tables
list while code which were opening this temporary table wasn't
always fulfilling this.
This patch changes code that opens new version of table to
always do this linking in. It also streamlines cleanup process
for cases when error occurs while we have new version of table
open.
******
WL#3726 "DDL locking for all metadata objects"
Add libmysqld/mdl.cc to .bzrignore.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.6
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sun 2008-05-25 00:33:22 +0400
message:
WL#3726 "DDL locking for all metadata objects".
Addition to the fix of assert failures in kill.test caused by
changes for this worklog.
Make sure we close the new table only once.
.bzrignore:
Add libmysqld/mdl.cc
libmysqld/CMakeLists.txt:
Added mdl.cc to the list of files needed for building of libmysqld.
libmysqld/Makefile.am:
Added files implementing new meta-data locking subsystem to the server.
mysql-test/include/handler.inc:
Use separate connection for waiting while threads performing DDL
operations conflicting with open HANDLER tables reach blocked
state. This is required because now we check and close tables open
by HANDLER statements in this connection conflicting with DDL in
another each time open_tables() is called and thus select from I_S
which is used for waiting will unblock DDL operations if issued
from connection with open HANDLERs.
mysql-test/r/create.result:
Adjusted test case after change in implementation of CREATE TABLE
... SELECT. We no longer have special check in open_table() which
catches the case when we select from the table created. Instead we
rely on unique_table() call which happens after opening and
locking all tables.
mysql-test/r/flush.result:
FLUSH TABLES WITH READ LOCK can no longer happen under LOCK
TABLES. Updated test accordingly.
mysql-test/r/flush_table.result:
Under LOCK TABLES we no longer allow to do FLUSH TABLES for tables
locked for read. Updated test accordingly.
mysql-test/r/handler_innodb.result:
Use separate connection for waiting while threads performing DDL
operations conflicting with open HANDLER tables reach blocked
state. This is required because now we check and close tables open
by HANDLER statements in this connection conflicting with DDL in
another each time open_tables() is called and thus select from I_S
which is used for waiting will unblock DDL operations if issued
from connection with open HANDLERs.
mysql-test/r/handler_myisam.result:
Use separate connection for waiting while threads performing DDL
operations conflicting with open HANDLER tables reach blocked
state. This is required because now we check and close tables open
by HANDLER statements in this connection conflicting with DDL in
another each time open_tables() is called and thus select from I_S
which is used for waiting will unblock DDL operations if issued
from connection with open HANDLERs.
mysql-test/r/information_schema.result:
Additional test for WL#3726 "DDL locking for all metadata
objects". Check that we use high-priority metadata lock requests
when filling I_S tables.
Rearrange tests to match 6.0 better (fewer merge conflicts).
mysql-test/r/kill.result:
Added tests checking that DDL and DML statements waiting for
metadata locks can be interrupted by KILL command.
mysql-test/r/lock.result:
One no longer is allowed to do DROP VIEW under LOCK TABLES even if
this view is locked by LOCK TABLES. The problem is that in such
situation write locks on view are not mutually exclusive so
upgrading metadata lock which is required for dropping of view
will lead to deadlock.
mysql-test/r/partition_column_prune.result:
Update results (same results in 6.0), WL#3726
mysql-test/r/partition_pruning.result:
Update results (same results in 6.0), WL#3726
mysql-test/r/ps_ddl.result:
We no longer invalidate prepared CREATE TABLE ... SELECT statement
if target table changes. This is OK since it is not strictly
necessary.
The first change is wrong, is caused by FLUSH TABLE
now flushing all unused tables. This is a regression that
Dmitri fixed in 6.0 in a follow up patch.
mysql-test/r/sp.result:
Under LOCK TABLES we no longer allow accessing views which were
not explicitly locked. To access view we need to obtain metadata
lock on it and doing this under LOCK TABLES may lead to deadlocks.
mysql-test/r/view.result:
One no longer is allowed to do DROP VIEW under LOCK TABLES even if
this view is locked by LOCK TABLES. The problem is that in such
situation even "write locks" on view are not mutually exclusive so
upgrading metadata lock which is required for dropping of view
will lead to deadlock
mysql-test/r/view_grant.result:
ALTER VIEW implementation was changed to open a view only after
checking that user which does alter has appropriate privileges on
it. This means that in case when user's privileges are
insufficient for this we won't check that new view definer is the
same as original one or user performing alter has SUPER privilege.
Adjusted test case accordingly.
mysql-test/r/view_multi.result:
Added test case for bug#25144 "replication / binlog with view
breaks".
mysql-test/suite/rpl/t/disabled.def:
Disable test for deprecated features (they don't work with new MDL).
mysql-test/t/create.test:
Adjusted test case after change in implementation of CREATE TABLE
... SELECT. We no longer have special check in open_table() which
catches the case when we select from the table created. Instead we
rely on unique_table() call which happens after opening and
locking all tables.
mysql-test/t/disabled.def:
Disable merge.test, subject of WL#4144
mysql-test/t/flush.test:
FLUSH TABLES WITH READ LOCK can no longer happen under LOCK
TABLES. Updated test accordingly.
mysql-test/t/flush_table.test:
Under LOCK TABLES we no longer allow to do FLUSH TABLES for tables
locked for read. Updated test accordingly.
mysql-test/t/information_schema.test:
Additional test for WL#3726 "DDL locking for all metadata
objects". Check that we use high-priority metadata lock requests
when filling I_S tables.
Rearrange the results for easier merges with 6.0.
mysql-test/t/kill.test:
Added tests checking that DDL and DML statements waiting for
metadata locks can be interrupted by KILL command.
mysql-test/t/lock.test:
One no longer is allowed to do DROP VIEW under LOCK TABLES even if
this view is locked by LOCK TABLES. The problem is that in such
situation write locks on view are not mutually exclusive so
upgrading metadata lock which is required for dropping of view
will lead to deadlock.
mysql-test/t/lock_multi.test:
Adjusted test case to the changes of status in various places
caused by change in implementation FLUSH TABLES WITH READ LOCK,
which is now takes global metadata lock before flushing tables and
therefore waits on at these places.
mysql-test/t/ps_ddl.test:
We no longer invalidate prepared CREATE TABLE ... SELECT statement
if target table changes. This is OK since it is not strictly
necessary.
The first change is wrong, is caused by FLUSH TABLE
now flushing all unused tables. This is a regression that
Dmitri fixed in 6.0 in a follow up patch.
mysql-test/t/sp.test:
Under LOCK TABLES we no longer allow accessing views which were
not explicitly locked. To access view we need to obtain metadata
lock on it and doing this under LOCK TABLES may lead to deadlocks.
mysql-test/t/trigger_notembedded.test:
Adjusted test case to the changes of status in various places
caused by change in implementation FLUSH TABLES WITH READ LOCK,
which is now takes global metadata lock before flushing tables and
therefore waits on at these places.
mysql-test/t/view.test:
One no longer is allowed to do DROP VIEW under LOCK TABLES even if
this view is locked by LOCK TABLES. The problem is that in such
situation even "write locks" on view are not mutually exclusive so
upgrading metadata lock which is required for dropping of view
will lead to deadlock.
mysql-test/t/view_grant.test:
ALTER VIEW implementation was changed to open a view only after
checking that user which does alter has appropriate privileges on
it. This means that in case when user's privileges are
insufficient for this we won't check that new view definer is the
same as original one or user performing alter has SUPER privilege.
Adjusted test case accordingly.
mysql-test/t/view_multi.test:
Added test case for bug#25144 "replication / binlog with view
breaks".
sql/CMakeLists.txt:
Added mdl.cc to the list of files needed for building of server.
sql/Makefile.am:
Added files implementing new meta-data locking subsystem to the
server.
sql/event_db_repository.cc:
Allocate metadata lock requests objects (MDL_LOCK) on execution
memory root in cases when TABLE_LIST objects is also allocated
there or on stack.
sql/ha_ndbcluster.cc:
Adjusted code to work nicely with new metadata locking subsystem.
close_cached_tables() no longer has wait_for_placeholder argument.
Instead of relying on this parameter and related behavior FLUSH
TABLES WITH READ LOCK now takes global shared metadata lock.
sql/ha_ndbcluster_binlog.cc:
Adjusted code to work with new metadata locking subsystem.
close_cached_tables() no longer has wait_for_placeholder argument.
Instead of relying on this parameter and related behavior FLUSH
TABLES WITH READ LOCK now takes global shared metadata lock.
sql/handler.cc:
update_frm_version():
Directly update TABLE_SHARE::mysql_version member instead of
going through all TABLE instances for this table (old code was a
legacy from pre-table-definition-cache days).
sql/lock.cc:
Use new metadata locking subsystem. Threw away most of functions
related to name locking as now one is supposed to use metadata
locking API instead. In lock_global_read_lock() and
unlock_global_read_lock() in order to avoid problems with global
read lock sneaking in at the moment when we perform FLUSH TABLES
or ALTER TABLE under LOCK TABLES and when tables being reopened
are protected only by metadata locks we also have to take global
shared meta data lock.
sql/log_event.cc:
Adjusted code to work with new metadata locking subsystem. For
tables open by slave thread for applying RBR events allocate
memory for lock request object in the same chunk of memory as
TABLE_LIST objects for them. In order to ensure that we keep these
objects around until tables are open always close tables before
calling Relay_log_info::clear_tables_to_lock(). Use new auxiliary
Relay_log_info::slave_close_thread_tables() method to enforce
this.
sql/log_event_old.cc:
Adjusted code to work with new metadata locking subsystem. Since
for tables open by slave thread for applying RBR events memory for
lock request object is allocated in the same chunk of memory as
TABLE_LIST objects for them we have to ensure that we keep these
objects around until tables are open. To ensure this we always
close tables before calling
Relay_log_info::clear_tables_to_lock(). To enfore this we use
new auxiliary Relay_log_info::slave_close_thread_tables()
method.
sql/mdl.cc:
Implemented new metadata locking subsystem and API described in
WL3726 "DDL locking for all metadata objects".
sql/mdl.h:
Implemented new metadata locking subsystem and API described in
WL3726 "DDL locking for all metadata objects".
sql/mysql_priv.h:
- close_thread_tables()/close_tables_for_reopen() now has one more
argument which indicates that metadata locks should be released
but not removed from the context in order to be used later in
mdl_wait_for_locks() and tdc_wait_for_old_version().
- close_cached_table() routine is no longer public.
- Thread waiting in wait_while_table_is_used() can be now killed
so this function returns boolean to make caller aware of such
situation.
- We no longer have table cache as separate entity instead used
and unused TABLE instances are linked to TABLE_SHARE objects in
table definition cache.
- Now third argument of open_table() is also used for requesting
table repair or auto-discovery of table's new definition. So its
type was changed from bool to enum.
- Added tdc_open_view() function for opening view by getting its
definition from disk (and table cache in future).
- reopen_name_locked_table() no longer needs "link_in" argument as
now we have exclusive metadata locks instead of dummy TABLE
instances when this function is called.
- find_locked_table() now takes head of list of TABLE instances
instead of always scanning through THD::open_tables list. Also
added find_write_locked_table() auxiliary.
- reopen_tables(), close_cached_tables() no longer have
mark_share_as_old and wait_for_placeholder arguments. Instead of
relying on this parameters and related behavior FLUSH TABLES
WITH READ LOCK now takes global shared metadata lock.
- We no longer need drop_locked_tables() and
abort_locked_tables().
- mysql_ha_rm_tables() now always assume that LOCK_open is not
acquired by caller.
- Added notify_thread_having_shared_lock() callback invoked by
metadata locking subsystem when acquiring an exclusive lock, for
each thread that has a conflicting shared metadata lock.
- Introduced expel_table_from_cache() as replacement for
remove_table_from_cache() (the main difference is that this new
function assumes that caller follows metadata locking protocol
and never waits).
- Threw away most of functions related to name locking. One should
use new metadata locking subsystem and API instead.
sql/mysqld.cc:
Got rid of call initializing/deinitializing table cache since now
it is embedded into table definition cache. Added calls for
initializing/ deinitializing metadata locking subsystem.
sql/rpl_rli.cc:
Introduced auxiliary Relay_log_info::slave_close_thread_tables()
method which is used for enforcing that we always close tables
open for RBR before deallocating TABLE_LIST elements and MDL_LOCK
objects for them.
sql/rpl_rli.h:
Introduced auxiliary Relay_log_info::slave_close_thread_tables()
method which is used for enforcing that we always close tables
open for RBR before deallocating TABLE_LIST elements and MDL_LOCK
objects for them.
sql/set_var.cc:
close_cached_tables() no longer has wait_for_placeholder argument.
Instead of relying on this parameter and related behavior FLUSH
TABLES WITH READ LOCK now takes global shared metadata lock.
sql/sp_head.cc:
For tables added to the statement's table list by prelocking
algorithm we allocate these objects either on the same memory as
corresponding table list elements or on THD::locked_tables_root
(if we are building table list for LOCK TABLES).
sql/sql_acl.cc:
Allocate metadata lock requests objects (MDL_LOCK) on execution
memory root in cases when we use stack TABLE_LIST objects to open
tables. Got rid of redundant code by using unlock_locked_tables()
function.
sql/sql_base.cc:
Changed code to use new MDL subsystem. Got rid of separate table
cache. Now used and unused TABLE instances are linked to the
TABLE_SHAREs in table definition cache.
check_unused():
Adjusted code to the fact that we no longer have separate table
cache. Removed dead code.
table_def_free():
Free TABLE instances referenced from TABLE_SHARE objects before
destroying table definition cache.
get_table_share():
Added assert which ensures that noone will be able to access
table (and its share) without acquiring some kind of metadata
lock first.
close_handle_and_leave_table_as_lock():
Adjusted code to the fact that TABLE instances now are linked to
list in TABLE_SHARE.
list_open_tables():
Changed this function to use table definition cache instead of
table cache.
free_cache_entry():
Unlink freed TABLE elements from the list of all TABLE instances
for the table in TABLE_SHARE.
kill_delayed_thread_for_table():
Added auxiliary for killing delayed insert threads for
particular table.
close_cached_tables():
Got rid of wait_for_refresh argument as we now rely on global
shared metadata lock to prevent FLUSH WITH READ LOCK sneaking in
when we are reopening tables. Heavily reworked this function to
use new MDL code and not to rely on separate table cache entity.
close_open_tables():
We no longer have separate table cache.
close_thread_tables():
Release metadata locks after closing all tables. Added skip_mdl
argument which allows us not to remove metadata lock requests
from the context in case when we are going to use this requests
later in mdl_wait_for_locks() and tdc_wait_for_old_versions().
close_thread_table()/close_table_for_reopen():
Since we no longer have separate table cache and all TABLE
instances are linked to TABLE_SHARE objects in table definition
cache we have to link/unlink TABLE object to/from appropriate
lists in the share.
name_lock_locked_table():
Moved redundant code to find_write_locked_table() function and
adjusted code to the fact that wait_while_table_is_used() can
now return with an error if our thread is killed.
reopen_table_entry():
We no longer need "link_in" argument as with MDL we no longer
call this function with dummy TABLE object pre-allocated and
added to the THD::open_tables. Also now we add newly-open TABLE
instance to the list of share's used TABLE instances.
table_cache_insert_placeholder():
Got rid of name-locking legacy.
lock_table_name_if_not_cached():
Moved to sql_table.cc the only place where it is used. It was
also reimplemented using new MDL API.
open_table():
- Reworked this function to use new MDL subsystem.
- Changed code to deal with table definition cache directly
instead of going through separate table cache.
- Now third argument is also used for requesting table repair
or auto-discovery of table's new definition. So its type was
changed from bool to enum.
find_locked_table()/find_write_locked_table():
Accept head of list of TABLE objects as first argument and use
this list instead of always searching in THD::open_tables list.
Also added auxiliary for finding write-locked locked tables.
reopen_table():
Adjusted function to work with new MDL subsystem and to properly
manuipulate with lists of used/unused TABLE instaces in
TABLE_SHARE.
reopen_tables():
Removed mark_share_as_old parameter. Instead of relying on it
and related behavior FLUSH TABLES WITH READ LOCK now takes
global shared metadata lock. Changed code after removing
separate table cache.
drop_locked_tables()/abort_locked_tables():
Got rid of functions which are no longer needed.
unlock_locked_tables():
Moved this function from sql_parse.cc and changed it to release
memory which was used for allocating metadata lock requests for
tables open and locked by LOCK TABLES.
tdc_open_view():
Intoduced function for opening a view by getting its definition
from disk (and table cache in future).
reopen_table_entry():
Introduced function for opening table definitions while holding
exclusive metatadata lock on it.
open_unireg_entry():
Got rid of this function. Most of its functionality is relocated
to open_table() and open_table_fini() functions, and some of it
to reopen_table_entry() and tdc_open_view(). Also code
resposible for auto-repair and auto-discovery of tables was
moved to separate function.
open_table_entry_fini():
Introduced function which contains common actions which finalize
process of TABLE object creation.
auto_repair_table():
Moved code responsible for auto-repair of table being opened
here.
handle_failed_open_table_attempt()
Moved code responsible for handling failing attempt to open
table to one place (retry due to lock conflict/old version,
auto-discovery and repair).
open_tables():
- Flush open HANDLER tables if they have old version of if there
is conflicting metadata lock against them (before this moment
we had this code in open_table()).
- When we open view which should be processed via derived table
on the second execution of prepared statement or stored
routine we still should call open_table() for it in order to
obtain metadata lock on it and prepare its security context.
- In cases when we discover that some special handling of
failure to open table is needed call
handle_failed_open_table_attempt() which handles all such
scenarios.
open_ltable():
Handling of various special scenarios of failure to open a table
was moved to separate handle_failed_open_table_attempt()
function.
remove_db_from_cache():
Removed this function as it is no longer used.
notify_thread_having_shared_lock():
Added callback which is invoked by MDL subsystem when acquiring
an exclusive lock, for each thread that has a conflicting shared
metadata lock.
expel_table_from_cache():
Introduced function for removing unused TABLE instances. Unlike
remove_table_from_cache() it relies on caller following MDL
protocol and having appropriate locks when calling it and thus
does not do any waiting if table is still in use.
tdc_wait_for_old_version():
Added function which allows open_tables() to wait in cases when
we discover that we should back-off due to presence of old
version of table.
abort_and_upgrade_lock():
Use new MDL calls.
mysql_wait_completed_table():
Got rid of unused function.
open_system_tables_for_read/for_update()/performance_schema_table():
Allocate MDL_LOCK objects on execution memory root in cases when
TABLE_LIST objects for corresponding tables is allocated on
stack.
close_performance_schema_table():
Release metadata locks after closing tables.
******
Use I_P_List for free/used tables list in the table share.
sql/sql_binlog.cc:
Use Relay_log_info::slave_close_thread_tables() method to enforce
that we always close tables open for RBR before deallocating
TABLE_LIST elements and MDL_LOCK objects for them.
sql/sql_class.cc:
Added meta-data locking contexts as part of Open_tables_state
context. Also introduced THD::locked_tables_root memory root
which is to be used for allocating MDL_LOCK objects for tables in
LOCK TABLES statement (end of lifetime for such objects is UNLOCK
TABLES so we can't use statement or execution root for them).
sql/sql_class.h:
Added meta-data locking contexts as part of Open_tables_state
context. Also introduced THD::locked_tables_root memory root
which is to be used for allocating MDL_LOCK objects for tables in
LOCK TABLES statement (end of lifetime for such objects is UNLOCK
TABLES so we can't use statement or execution root for them).
Note: handler_mdl_context and locked_tables_root and
mdl_el_root will be removed by subsequent patches.
sql/sql_db.cc:
mysql_rm_db() does not really need to call remove_db_from_cache()
as it drops each table in the database using
mysql_rm_table_part2(), which performs all necessary operations on
table (definition) cache.
sql/sql_delete.cc:
Use the new metadata locking API for TRUNCATE.
sql/sql_handler.cc:
Changed HANDLER implementation to use new metadata locking
subsystem. Note that MDL_LOCK objects for HANDLER tables are
allocated in the same chunk of heap memory as TABLE_LIST object
for those tables.
sql/sql_insert.cc:
mysql_insert():
find_locked_table() now takes head of list of TABLE object as
its argument instead of always scanning through THD::open_tables
list.
handle_delayed_insert():
Allocate metadata lock request object for table open by delayed
insert thread on execution memroot. create_table_from_items():
We no longer allocate dummy TABLE objects for tables being
created if they don't exist. As consequence
reopen_name_locked_table() no longer has link_in argument.
open_table() now has one more argument which is not relevant for
temporary tables.
sql/sql_parse.cc:
- Moved unlock_locked_tables() routine to sql_base.cc and made
available it in other files. Got rid of some redundant code by
using this function.
- Replaced boolean TABLE_LIST::create member with enum
open_table_type member.
- Use special memory root for allocating MDL_LOCK objects for
tables open and locked by LOCK TABLES (these object should live
till UNLOCK TABLES so we can't allocate them on statement nor
execution memory root). Also properly set metadata lock
upgradability attribure for those tables.
- Under LOCK TABLES it is no longer allowed to flush tables which
are not write-locked as this breaks metadata locking protocol
and thus potentially might lead to deadlock.
- Added auxiliary adjust_mdl_locks_upgradability() function.
sql/sql_partition.cc:
Adjusted code to the fact that reopen_tables() no longer has
"mark_share_as_old" argument. Got rid of comments which are no
longer true.
sql/sql_plist.h:
Added I_P_List template class for parametrized intrusive doubly
linked lists and I_P_List_iterator for corresponding iterator.
Unlike for I_List<> list elements of such list can participate in
several lists. Unlike List<> such lists are doubly-linked and
intrusive.
sql/sql_plugin.cc:
Allocate metadata lock requests objects (MDL_LOCK) on execution
memory root in cases when we use stack TABLE_LIST objects to open
tables.
sql/sql_prepare.cc:
Replaced boolean TABLE_LIST::create member with enum
open_table_type member. This allows easily handle situation in
which instead of opening the table we want only to take exclusive
metadata lock on it.
sql/sql_rename.cc:
Use new metadata locking subsystem in implementation of RENAME
TABLE.
sql/sql_servers.cc:
Allocate metadata lock requests objects (MDL_LOCK) on execution
memory root in cases when we use stack TABLE_LIST objects to open
tables. Got rid of redundant code by using unlock_locked_tables()
function.
sql/sql_show.cc:
Acquire shared metadata lock when we are getting information for
I_S table directly from TABLE_SHARE without doing full-blown table
open. We use high priority lock request in this situation in
order to avoid deadlocks.
Also allocate metadata lock requests objects (MDL_LOCK) on
execution memory root in cases when TABLE_LIST objects are also
allocated there
sql/sql_table.cc:
mysql_rm_table():
Removed comment which is no longer relevant.
mysql_rm_table_part2():
Now caller of mysql_ha_rm_tables() should not own LOCK_open.
Adjusted code to use new metadata locking subsystem instead of
name-locks.
lock_table_name_if_not_cached():
Moved this function from sql_base.cc to this file and
reimplemented it using metadata locking API.
mysql_create_table():
Adjusted code to use new MDL API.
wait_while_table_is_used():
Changed function to use new MDL subsystem. Made thread waiting
in it killable (this also led to introduction of return value so
caller can distinguish successful executions from situations
when waiting was aborted).
close_cached_tables():
Thread waiting in this function is killable now. As result it
has return value for distinguishing between succes and failure.
Got rid of redundant boradcast_refresh() call.
prepare_for_repair():
Use MDL subsystem instead of name-locks.
mysql_admin_table():
mysql_ha_rm_tables() now always assumes that caller doesn't own
LOCK_open.
mysql_repair_table():
We should mark all elements of table list as requiring
upgradable metadata locks.
mysql_create_table_like():
Use new MDL subsystem instead of name-locks.
create_temporary_tables():
We don't need to obtain metadata locks when creating temporary
table.
mysql_fast_or_online_alter_table():
Thread waiting in wait_while_table_is_used() is now killable.
mysql_alter_table():
Adjusted code to work with new MDL subsystem and to the fact
that threads waiting in what_while_table_is_used() and
close_cached_table() are now killable.
sql/sql_test.cc:
We no longer have separate table cache. TABLE instances are now
associated with/linked to TABLE_SHARE objects in table definition
cache.
sql/sql_trigger.cc:
Adjusted code to work with new metadata locking subsystem. Also
reopen_tables() no longer has mark_share_as_old argument (Instead
of relying on this parameter and related behavior FLUSH TABLES
WITH READ LOCK now takes global shared metadata lock).
sql/sql_udf.cc:
Allocate metadata lock requests objects (MDL_LOCK) on execution
memory root in cases when we use stack TABLE_LIST objects to open
tables.
sql/sql_update.cc:
Adjusted code to work with new meta-data locking subsystem.
sql/sql_view.cc:
Added proper meta-data locking to implementations of
CREATE/ALTER/DROP VIEW statements. Now we obtain exclusive
meta-data lock on a view before creating/ changing/dropping it.
This ensures that all concurrent statements that use this view
will finish before our statement will proceed and therefore we
will get correct order of statements in the binary log.
Also ensure that TABLE_LIST::mdl_upgradable attribute is properly
propagated for underlying tables of view.
sql/table.cc:
Added auxiliary alloc_mdl_locks() function for allocating metadata
lock request objects for all elements of table list.
sql/table.h:
TABLE_SHARE:
Got rid of unused members. Introduced members for storing lists
of used and unused TABLE objects for this share.
TABLE:
Added members for linking TABLE objects into per-share lists of
used and unused TABLE instances. Added member for holding
pointer to metadata lock for this table.
TABLE_LIST:
Replaced boolean TABLE_LIST::create member with enum
open_table_type member. This allows easily handle situation in
which instead of opening the table we want only to take
exclusive meta-data lock on it (we need this in order to handle
ALTER VIEW and CREATE VIEW statements).
Introduced new mdl_upgradable member for marking elements of
table list for which we need to take upgradable shared metadata
lock instead of plain shared metadata lock. Added pointer for
holding pointer to MDL_LOCK for the table.
Added auxiliary alloc_mdl_locks() function for allocating metadata
lock requests objects for all elements of table list. Added
auxiliary set_all_mdl_upgradable() function for marking all
elements in table list as requiring upgradable metadata locks.
storage/myisammrg/ha_myisammrg.cc:
Allocate MDL_LOCK objects for underlying tables of MERGE table.
To be reworked once Ingo pushes his patch for WL4144.
|
||
|
Konstantin Osipov
|
9a9e8d2311 |
Backport of:
---------------------------------------------------------------------- ChangeSet@1.2571, 2008-04-08 12:30:06+02:00, vvaintroub@wva. +122 -0 Bug#32082 : definition of VOID in my_global.h conflicts with Windows SDK headers VOID macro is now removed. Its usage is replaced with void cast. In some cases, where cast does not make much sense (pthread_*, printf, hash_delete, my_seek), cast is ommited. client/mysqladmin.cc: Bug#32082 : remove VOID macro client/mysqldump.c: Bug#32082 : remove VOID macro client/mysqlimport.c: Bug#32082 : remove VOID macro client/mysqlslap.c: Bug#32082 : remove VOID macro client/mysqltest.cc: Bug#32082 : remove VOID macro client/sql_string.cc: Bug#32082 : remove VOID macro extra/comp_err.c: Bug#32082 : remove VOID macro extra/replace.c: Bug#32082 : remove VOID macro include/my_alarm.h: Bug#32082 : remove VOID macro include/my_global.h: Bug#32082 : remove VOID macro libmysql/libmysql.c: Bug#32082 : remove VOID macro mysys/errors.c: Bug#32082 : remove VOID macro mysys/hash.c: Bug#32082 : remove VOID macro mysys/mf_iocache2.c: Bug#32082 : remove VOID macro mysys/mf_loadpath.c: Bug#32082 : remove VOID macro mysys/mf_path.c: Bug#32082 : remove VOID macro mysys/my_append.c: Bug#32082 : remove VOID macro mysys/my_clock.c: Bug#32082 : remove VOID macro mysys/my_copy.c: Bug#32082 : remove VOID macro mysys/my_fstream.c: Bug#32082 : remove VOID macro mysys/my_getwd.c: Bug#32082 : remove VOID macro mysys/my_lib.c: Bug#32082 : remove VOID macro mysys/my_lockmem.c: Bug#32082 : remove VOID macro mysys/my_pthread.c: Bug#32082 : remove VOID macro mysys/my_redel.c: Bug#32082 : remove VOID macro mysys/stacktrace.c: Bug#32082 : remove VOID macro mysys/thr_alarm.c: Bug#32082 : remove VOID macro mysys/thr_lock.c: Bug#32082 : remove VOID macro sql/derror.cc: Bug#32082 : remove VOID macro sql/des_key_file.cc: Bug#32082 : remove VOID macro sql/discover.cc: Bug#32082 : remove VOID macro sql/field.cc: Bug#32082 : remove VOID macro sql/filesort.cc: Bug#32082 : remove VOID macro sql/ha_ndbcluster.cc: Bug#32082 : remove VOID macro sql/ha_partition.cc: Bug#32082 : remove VOID macro sql/handler.cc: Bug#32082 : remove VOID macro sql/hostname.cc: Bug#32082 : remove VOID macro sql/init.cc: Bug#32082 : remove VOID macro sql/item.cc: Bug#32082 : remove VOID macro sql/item_cmpfunc.cc: Bug#32082 : remove VOID macro sql/item_strfunc.cc: Bug#32082 : remove VOID macro sql/lock.cc: Bug#32082 : remove VOID macro sql/log.cc: Bug#32082 : remove VOID macro sql/log_event.cc: Bug#32082 : remove VOID macro sql/mysqld.cc: Bug#32082 : remove VOID macro sql/opt_range.h: Bug#32082 : remove VOID macro sql/protocol.cc: Bug#32082 : remove VOID macro sql/records.cc: Bug#32082 : remove VOID macro sql/sp_head.cc: Bug#32082 : remove VOID macro sql/sp_pcontext.cc: Bug#32082 : remove VOID macro sql/sql_acl.cc: Bug#32082 : remove VOID macro sql/sql_base.cc: Bug#32082 : remove VOID macro sql/sql_cache.cc: Bug#32082 : remove VOID macro sql/sql_connect.cc: Bug#32082 : remove VOID macro sql/sql_db.cc: Bug#32082 : remove VOID macro sql/sql_delete.cc: Bug#32082 : remove VOID macro sql/sql_handler.cc: Bug#32082 : remove VOID macro sql/sql_insert.cc: Bug#32082 : remove VOID macro sql/sql_map.cc: Bug#32082 : remove VOID macro sql/sql_parse.cc: Bug#32082 : remove VOID macro sql/sql_select.cc: Bug#32082 : remove VOID macro sql/sql_servers.cc: Bug#32082 : remove VOID macro sql/sql_show.cc: Bug#32082 : remove VOID macro sql/sql_string.cc: Bug#32082 : remove VOID macro sql/sql_table.cc: Bug#32082 : remove VOID macro sql/sql_test.cc: Bug#32082 : remove VOID macro sql/sql_trigger.cc: Bug#32082 : remove VOID macro sql/sql_update.cc: Bug#32082 : remove VOID macro sql/sql_view.cc: Bug#32082 : remove VOID macro sql/table.cc: Bug#32082 : remove VOID macro sql/tztime.cc: Bug#32082 : remove VOID macro sql/udf_example.c: Bug#32082 : remove VOID macro sql/uniques.cc: Bug#32082 : remove VOID macro sql/unireg.cc: Bug#32082 : remove VOID macro storage/archive/ha_archive.cc: Bug#32082 : remove VOID macro storage/blackhole/ha_blackhole.cc: Bug#32082 : remove VOID macro storage/csv/ha_tina.cc: Bug#32082 : remove VOID macro storage/csv/transparent_file.cc: Bug#32082 : remove VOID macro storage/example/ha_example.cc: Bug#32082 : remove VOID macro storage/federated/ha_federated.cc: Bug#32082 : remove VOID macro storage/heap/hp_clear.c: Bug#32082 : remove VOID macro storage/heap/hp_create.c: Bug#32082 : remove VOID macro storage/heap/hp_test1.c: Bug#32082 : remove VOID macro storage/heap/hp_test2.c: Bug#32082 : remove VOID macro storage/innobase/handler/ha_innodb.cc: Bug#32082 : remove VOID macro storage/myisam/ft_eval.c: Bug#32082 : remove VOID macro storage/myisam/ha_myisam.cc: Bug#32082 : remove VOID macro storage/myisam/mi_changed.c: Bug#32082 : remove VOID macro storage/myisam/mi_check.c: Bug#32082 : remove VOID macro storage/myisam/mi_close.c: Bug#32082 : remove VOID macro storage/myisam/mi_create.c: Bug#32082 : remove VOID macro storage/myisam/mi_dbug.c: Bug#32082 : remove VOID macro storage/myisam/mi_delete.c: Bug#32082 : remove VOID macro storage/myisam/mi_delete_all.c: Bug#32082 : remove VOID macro storage/myisam/mi_dynrec.c: Bug#32082 : remove VOID macro storage/myisam/mi_info.c: Bug#32082 : remove VOID macro storage/myisam/mi_locking.c: Bug#32082 : remove VOID macro storage/myisam/mi_log.c: Bug#32082 : remove VOID macro storage/myisam/mi_open.c: Bug#32082 : remove VOID macro storage/myisam/mi_packrec.c: Bug#32082 : remove VOID macro storage/myisam/mi_panic.c: Bug#32082 : remove VOID macro storage/myisam/mi_rsame.c: Bug#32082 : remove VOID macro storage/myisam/mi_statrec.c: Bug#32082 : remove VOID macro storage/myisam/mi_test1.c: Bug#32082 : remove VOID macro storage/myisam/mi_test2.c: Bug#32082 : remove VOID macro storage/myisam/mi_test3.c: Bug#32082 : remove VOID macro storage/myisam/mi_update.c: Bug#32082 : remove VOID macro storage/myisam/mi_write.c: Bug#32082 : remove VOID macro storage/myisam/myisamchk.c: Bug#32082 : remove VOID macro storage/myisam/myisamlog.c: Bug#32082 : remove VOID macro storage/myisam/myisampack.c: Bug#32082 : remove VOID macro storage/myisam/sort.c: Bug#32082 : remove VOID macro storage/myisammrg/myrg_close.c: Bug#32082 : remove VOID macro storage/myisammrg/myrg_create.c: Bug#32082 : remove VOID macro storage/myisammrg/myrg_open.c: Bug#32082 : remove VOID macro strings/str_test.c: Bug#32082 : remove VOID macro tests/thread_test.c: Bug#32082 : remove VOID macro |
||
|
Konstantin Osipov
|
1b34d593b5 |
Backport of:
------------------------------------------------------------ revno: 2476.784.3 committer: davi@moksha.local timestamp: Tue 2007-10-02 21:27:31 -0300 message: Bug#25858 Some DROP TABLE under LOCK TABLES can cause deadlocks When a client (connection) holds a lock on a table and attempts to drop (obtain a exclusive lock) on a second table that is already held by a second client and the second client then attempts to drop the table that is held by the first client, leads to a circular wait deadlock. This scenario is very similar to trying to drop (or rename) a table while holding read locks and are correctly forbidden. The solution is to allow a drop table operation to continue only if the table being dropped is write (exclusively) locked, or if the table is temporary, or if the client is not holding any locks. Using this scheme prevents the creation of a circular chain in which each client is waiting for one table that the next client in the chain is holding. This is incompatible change, as can be seen by number of tests cases that needed to be fixed, but is consistent with respect to behavior of the different scenarios in which the circular wait might happen. mysql-test/r/drop.result: Test case result for Bug#25858 mysql-test/r/group_by.result: Fix test case result wrt drop table under lock tables -- unlock tables before dropping table. mysql-test/r/insert_notembedded.result: Fix test case result wrt drop table under lock tables -- unlock tables before dropping table mysql-test/r/lock.result: Fix test case result wrt drop table under lock tables -- unlock tables before dropping table. mysql-test/r/lock_multi.result: Fix test case result wrt drop table under lock tables -- unlock tables before dropping table. mysql-test/r/myisam.result: Fix test case result wrt drop table under lock tables -- unlock tables before dropping table. mysql-test/r/view.result: Fix test case result wrt drop table under lock tables -- unlock tables before dropping table. mysql-test/t/drop.test: Add test case for Bug#25858 mysql-test/t/group_by.test: Fix test case: unlock tables in preparation for a drop table. In some circumstances, dropping tables while holding locks leads to a deadlock. mysql-test/t/insert_notembedded.test: Fix test case: unlock tables in preparation for a drop table. In some circumstances, dropping tables while holding locks leads to a deadlock. mysql-test/t/lock.test: Fix test case: unlock tables in preparation for a drop table. In some circumstances, dropping tables while holding locks leads to a deadlock. mysql-test/t/lock_multi.test: Fix test case: unlock tables in preparation for a drop table. In some circumstances, dropping tables while holding locks leads to a deadlock. mysql-test/t/myisam.test: Fix test case: unlock tables in preparation for a drop table. In some circumstances, dropping tables while holding locks leads to a deadlock. mysql-test/t/query_cache_notembedded.test: Fix test case: unlock tables in preparation for a drop table. In some circumstances, dropping tables while holding locks leads to a deadlock. mysql-test/t/view.test: Fix test case: unlock tables in preparation for a drop table. In some circumstances, dropping tables while holding locks leads to a deadlock. sql/lock.cc: When trying to obtain a name lock under lock tables, ensure that the table is properly exclusively locked and fail otherwise. |
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Konstantin Osipov
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fcf6c1548e |
Backport of:
revno: 2476.784.2 committer: davi@moksha.local timestamp: Thu 2007-09-27 16:56:27 -0300 message: Bug#28870 check that table locks are released/reset The problem is that some mysql_lock_tables error paths are not resetting the tables lock type back to TL_UNLOCK. If the lock types are not reset properly, a table might be returned to the table cache with wrong lock_type. The proposed fix is to ensure that the tables lock type is always properly reset when mysql_lock_tables fails. This is a incompatible change with respect to the process state information. sql/lock.cc: Merge mysql_lock_tables cleanup sequence and the reset_lock_data function into a single function and take steps to ensure it is always called for each error exit path. Also remove references to the redundant THD::locked variable which was almost exclusively used by this function and the same information is already on proc_info. sql/sql_class.cc: Remove references to the THD::locked variable. sql/sql_class.h: Remove the THD::locked variable. sql/sql_show.cc: Remove references to THD:locked, state_info will now default to proc_info. |
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unknown
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6aad537a6a | Merge MySQL 5.1.39 into MariaDB 5.1. | ||
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Konstantin Osipov
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9b41c7532d |
Backport of:
---------------------------------------------------------- revno: 2617.22.5 committer: Konstantin Osipov <kostja@sun.com> branch nick: mysql-6.0-runtime timestamp: Tue 2009-01-27 05:08:48 +0300 message: Remove non-prefixed use of HASH. Always use my_hash_init(), my_hash_inited(), my_hash_search(), my_hash_element(), my_hash_delete(), my_hash_free() rather than non-prefixed counterparts (hash_init(), etc). Remove the backward-compatible defines. |
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Staale Smedseng
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5be4c38226 | Merge from 5.0 for 43414 | ||
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Staale Smedseng
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1ba25ae47c |
Bug #43414 Parenthesis (and other) warnings compiling MySQL
with gcc 4.3.2
This patch fixes a number of GCC warnings about variables used
before initialized. A new macro UNINIT_VAR() is introduced for
use in the variable declaration, and LINT_INIT() usage will be
gradually deprecated. (A workaround is used for g++, pending a
patch for a g++ bug.)
GCC warnings for unused results (attribute warn_unused_result)
for a number of system calls (present at least in later
Ubuntus, where the usual void cast trick doesn't work) are
also fixed.
client/mysqlmanager-pwgen.c:
A fix for warn_unused_result, adding fallback to use of
srand()/rand() if /dev/random cannot be used. Also actually
adds calls to rand() in the second branch so that it actually
creates a random password.
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Michael Widenius
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e726e587ec |
Merged with mysql-5.1 tree.
client/mysqltest.cc: Manually merged configure.in: Manually merged mysql-test/r/variables.result: Manually merged mysql-test/t/variables.test: Manually merged mysys/my_pread.c: Manually merged mysys/my_read.c: Manually merged sql/mysqld.cc: Manually merged storage/csv/ha_tina.h: Manually merged storage/myisam/ha_myisam.cc: Manually merged storage/myisam/mi_check.c: Manually merged storage/myisam/mi_search.c: Manually merged |
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Chad MILLER
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14f923c028 | Merge 5.0.80 release and 5.0 community. Version left at 5.0.80. | ||
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Michael Widenius
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a8fdaa6f2c |
Merge with base MySQL 5.1
Contains fixes for test cases Changed release tag to beta configure.in: change release tag to beta |
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Ignacio Galarza
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5b7347bda3 |
Bug#29125 Windows Server X64: so many compiler warnings
- Remove bothersome warning messages. This change focuses on the warnings that are covered by the ignore file: support-files/compiler_warnings.supp. - Strings are guaranteed to be max uint in length |
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Ignacio Galarza
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54fbbf9591 |
Bug#29125 Windows Server X64: so many compiler warnings
- Remove bothersome warning messages. This change focuses on the warnings that are covered by the ignore file: support-files/compiler_warnings.supp. - Strings are guaranteed to be max uint in length |
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Guilhem Bichot
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33b194c36e |
Merge of 5.1-main into 5.1-maria. There were no changes to storage/myisam, or mysql-test/t/*myisam*.
However there were three new tests mysql-test/suite/parts/t/partition*myisam.test, of which I make here copies for Maria. |
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Build Team
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e85fe79430 |
Added "Sun Microsystems, Inc." to copyright headers on files modified
since Oct 1st |
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Michael Widenius
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f47e003e1b | Merged 5.1 with maria 5.1 |