dict_table_close(): Fix a race condition around dict_stats_deinit().
This was not observed; it should have been caught by an assertion.
dict_stats_deinit(): Slightly simplify the code.
ha_innobase::info_low(): If the table is unreadable,
initialize some dummy statistics.
In the parent commit, dict_sys.latch could theoretically have been
replaced with a mutex. But, we can do better and merge dict_sys.mutex
into dict_sys.latch. Generally, every occurrence of dict_sys.mutex_lock()
will be replaced with dict_sys.lock().
The PERFORMANCE_SCHEMA instrumentation for dict_sys_mutex
will be removed along with dict_sys.mutex. The dict_sys.latch
will remain instrumented as dict_operation_lock.
Some use of dict_sys.lock() will be replaced with dict_sys.freeze(),
which we will reintroduce for the new shared mode. Most notably,
concurrent table lookups are possible as long as the tables are present
in the dict_sys cache. In particular, this will allow more concurrency
among InnoDB purge workers.
Because dict_sys.mutex will no longer 'throttle' the threads that purge
InnoDB transaction history, a performance degradation may be observed
unless innodb_purge_threads=1.
The table cache eviction policy will become FIFO-like,
similar to what happened to fil_system.LRU
in commit 45ed9dd957.
The name of the list dict_sys.table_LRU will become somewhat misleading;
that list contains tables that may be evicted, even though the
eviction policy no longer is least-recently-used but first-in-first-out.
(Note: Tables can never be evicted as long as locks exist on them or
the tables are in use by some thread.)
As demonstrated by the test perfschema.sxlock_func, there
will be less contention on dict_sys.latch, because some previous
use of exclusive latches will be replaced with shared latches.
fts_parse_sql_no_dict_lock(): Replaced with pars_sql().
fts_get_table_name_prefix(): Merged to fts_optimize_create().
dict_stats_update_transient_for_index(): Deduplicated some code.
ha_innobase::info_low(), dict_stats_stop_bg(): Use a combination
of dict_sys.latch and table->stats_mutex_lock() to cover the
changes of BG_STAT_SHOULD_QUIT, because the flag is being read
in dict_stats_update_persistent() while not holding dict_sys.latch.
row_discard_tablespace_for_mysql(): Protect stats_bg_flag by
exclusive dict_sys.latch, like most other code does.
row_quiesce_table_has_fts_index(): Remove unnecessary mutex
acquisition. FLUSH TABLES...FOR EXPORT is protected by MDL.
row_import::set_root_by_heuristic(): Remove unnecessary mutex
acquisition. ALTER TABLE...IMPORT TABLESPACE is protected by MDL.
row_ins_sec_index_entry_low(): Replace a call
to dict_set_corrupted_index_cache_only(). Reads of index->type
were not really protected by dict_sys.mutex, and writes
(flagging an index corrupted) should be extremely rare.
dict_stats_process_entry_from_defrag_pool(): Only freeze the dictionary,
do not lock it exclusively.
dict_stats_wait_bg_to_stop_using_table(), DICT_BG_YIELD: Remove trx.
We can simply invoke dict_sys.unlock() and dict_sys.lock() directly.
dict_acquire_mdl_shared()<trylock=false>: Assert that dict_sys.latch is
only held in shared more, not exclusive mode. Only acquire it in
exclusive mode if the table needs to be loaded to the cache.
dict_sys_t::acquire(): Remove. Relocating elements in dict_sys.table_LRU
would require holding an exclusive latch, which we want to avoid
for performance reasons.
dict_sys_t::allow_eviction(): Add the table first to dict_sys.table_LRU,
to compensate for the removal of dict_sys_t::acquire(). This function
is only invoked by INFORMATION_SCHEMA.INNODB_SYS_TABLESTATS.
dict_table_open_on_id(), dict_table_open_on_name(): If dict_locked=false,
try to acquire dict_sys.latch in shared mode. Only acquire the latch in
exclusive mode if the table is not found in the cache.
Reviewed by: Thirunarayanan Balathandayuthapani
In theory, read-only workload shouldn't have anything to do with
dict_sys mutex. dict_sys mutex is meant to protect database metadata.
But then why does dict_sys mutex shows up as part of a read-only workload?
This workload needs to fetch stats for query processing and while reading
these stats dict_sys mutex is taken.
Is this really needed?
No. For the traditional reasons, it was the default global mutex used.
Based on 10.6 changes, flow can now use table->lock_mutex to protect
update/access of these stats. table mutexes being table specific
global contention arising out of dict_sys is reduced.
Thanks to Marko Makela for his early suggestion around proposed alternative
and review of the draft patch.
SHOW ENGINE INNODB MUTEX functionality is completely removed,
as are the InnoDB latching order checks.
We will enforce innodb_fatal_semaphore_wait_threshold
only for dict_sys.mutex and lock_sys.mutex.
dict_sys_t::mutex_lock(): A single entry point for dict_sys.mutex.
lock_sys_t::mutex_lock(): A single entry point for lock_sys.mutex.
FIXME: srv_sys should be removed altogether; it is duplicating tpool
functionality.
fil_crypt_threads_init(): To prevent SAFE_MUTEX warnings, we must
not hold fil_system.mutex.
fil_close_all_files(): To prevent SAFE_MUTEX warnings for
fil_space_destroy_crypt_data(), we must not hold fil_system.mutex
while invoking fil_space_free_low() on a detached tablespace.
Patch removes dict_index_t::stats_latch. Table/index statistics now
protected with dict_sys->mutex. That way statistics computation can
happen in parallel in several threads and dict_sys->mutex will be locked
only for a short period of time.
This patch is a joint work with Marko Mäkelä
dict_index_t:🔒 make mutable which allows to pass const pointer
when only lock is touched in an object
btr_height_get()
btr_get_size(): make index argument const for better type safety
btr_estimate_number_of_different_key_vals(): now returns computed values
instead of setting fields in dict_index_t directly
remove everything related to dict_index_t::stats_latch
dict_stats_index_set_n_diff(): now returns computed values instead
of setting fields in dict_index_t directly
dict_stats_analyze_index(): now returns computed values instead
of setting fields in dict_index_t directly
Reviewed by: Marko Mäkelä
- Some of the bug fixes are backports from 10.5!
- The fix in innobase/fil/fil0fil.cc is just a backport to get less
error messages in mysqld.1.err when running with valgrind.
- Renamed HAVE_valgrind_or_MSAN to HAVE_valgrind
MemorySanitizer (clang -fsanitize=memory) requires that all code
be compiled with instrumentation enabled. The only exception is the
C runtime library. Failure to use instrumented libraries will cause
bogus messages about memory being uninitialized.
In WITH_MSAN builds, we must avoid calling getservbyname(),
because even though it is a standard library function, it is
not instrumented, not even in clang 10.
Note: Before MariaDB Server 10.5, ./mtr will typically fail
due to the old PCRE library, which was updated in MDEV-14024.
The following cmake options were tested on 10.5
in commit 94d0bb4dbe:
cmake \
-DCMAKE_C_FLAGS='-march=native -O2' \
-DCMAKE_CXX_FLAGS='-stdlib=libc++ -march=native -O2' \
-DWITH_EMBEDDED_SERVER=OFF -DWITH_UNIT_TESTS=OFF -DCMAKE_BUILD_TYPE=Debug \
-DWITH_INNODB_{BZIP2,LZ4,LZMA,LZO,SNAPPY}=OFF \
-DPLUGIN_{ARCHIVE,TOKUDB,MROONGA,OQGRAPH,ROCKSDB,CONNECT,SPIDER}=NO \
-DWITH_SAFEMALLOC=OFF \
-DWITH_{ZLIB,SSL,PCRE}=bundled \
-DHAVE_LIBAIO_H=0 \
-DWITH_MSAN=ON
MEM_MAKE_DEFINED(): An alias for VALGRIND_MAKE_MEM_DEFINED()
and __msan_unpoison().
MEM_GET_VBITS(), MEM_SET_VBITS(): Aliases for
VALGRIND_GET_VBITS(), VALGRIND_SET_VBITS(), __msan_copy_shadow().
InnoDB: Replace the UNIV_MEM_ macros with corresponding MEM_ macros.
ut_crc32_8_hw(), ut_crc32_64_low_hw(): Use the compiler built-in
functions instead of inline assembler when building WITH_MSAN.
This will require at least -msse4.2 when building for IA-32 or AMD64.
The inline assembler would not be instrumented, and would thus cause
bogus failures.
MemorySanitizer (clang -fsanitize=memory) requires that all code
be compiled with instrumentation enabled. The C runtime library
is an exception. Failure to use instrumented libraries will cause
bogus messages about memory being uninitialized.
In WITH_MSAN builds, we must avoid calling getservbyname(),
because even though it is a standard library function, it is
not instrumented, not even in clang 10.
The following cmake options were tested:
-DCMAKE_C_FLAGS='-march=native -O2'
-DCMAKE_CXX_FLAGS='-stdlib=libc++ -march=native -O2'
-DWITH_EMBEDDED_SERVER=OFF -DWITH_UNIT_TESTS=OFF -DCMAKE_BUILD_TYPE=Debug
-DWITH_INNODB_{BZIP2,LZ4,LZMA,LZO,SNAPPY}=OFF
-DPLUGIN_{ARCHIVE,TOKUDB,MROONGA,OQGRAPH,ROCKSDB,CONNECT,SPIDER}=NO
-DWITH_SAFEMALLOC=OFF
-DWITH_{ZLIB,SSL,PCRE}=bundled
-DHAVE_LIBAIO_H=0
-DWITH_MSAN=ON
MEM_MAKE_DEFINED(): An alias for VALGRIND_MAKE_MEM_DEFINED()
and in the future, __msan_unpoison().
For now, neither MEM_MAKE_DEFINED() nor MEM_UNDEFINED()
perform any action under MSAN. Enabling them will catch more bugs, but
will also require some more fixes or work-arounds.
Json_writer::add_double(): Work around a frequently occurring
failure in optimizer tests, related to EXPLAIN FORMAT=JSON.
dtoa(): Disable MSAN altogether. For some reason, this function
is triggering a lot of trouble, especially when invoked for
DBUG functions. The MDL default timeout is dd=86400 seconds,
and for some reason it is claimed to be uninitialized.
InnoDB: Define UNIV_DEBUG_VALGRIND also WITH_MSAN.
ut_crc32_8_hw(), ut_crc32_64_low_hw(): Use the compiler built-in
functions instead of inline assembler when building WITH_MSAN.
This will require at least -msse4.2 when building for IA-32 or AMD64.
The inline assembler would not be instrumented, and would thus cause
bogus failures.
dict_table_t::stats_latch_created: remove along with related stuff
dict_table_t::stats_latch: make value member, not pointer. And always lock this
for simplicity, even to stats cloned table.
based on the work of Sergey Vojtovich
dict_sys_t::create(): Renamed from dict_init().
dict_sys_t::close(): Renamed from dict_close().
dict_sys_t::add(): Sliced from dict_table_t::add_to_cache().
dict_sys_t::remove(): Renamed from dict_table_remove_from_cache().
dict_sys_t::prevent_eviction(): Renamed from
dict_table_move_from_lru_to_non_lru().
dict_sys_t::acquire(): Replaces dict_move_to_mru() and some more logic.
dict_sys_t::resize(): Renamed from dict_resize().
dict_sys_t::find(): Replaces dict_lru_find_table() and
dict_non_lru_find_table().
MDEV-14511 tried to avoid some consistency problems related to InnoDB
persistent statistics. The persistent statistics are being written by
an InnoDB internal SQL interpreter that requires the InnoDB data dictionary
cache to be locked.
Before MDEV-14511, the statistics were written during DDL in separate
transactions, which could unnecessarily reduce performance (each commit
would require a redo log flush) and break atomicity, because the statistics
would be updated separately from the dictionary transaction.
However, because it is unacceptable to hold the InnoDB data dictionary
cache locked while suspending the execution for waiting for a
transactional lock (in the mysql.innodb_index_stats or
mysql.innodb_table_stats tables) to be released, any lock conflict
was immediately be reported as "lock wait timeout".
To fix MDEV-14941, an attempt to reduce these lock conflicts by acquiring
transactional locks on the user tables in both the statistics and DDL
operations was made, but it would still not entirely prevent lock conflicts
on the mysql.innodb_index_stats and mysql.innodb_table_stats tables.
Fixing the remaining problems would require a change that is too intrusive
for a GA release series, such as MariaDB 10.2.
Thefefore, we revert the change MDEV-14511. To silence the
MDEV-13201 assertion, we use the pre-existing flag trx_t::internal.
dict_stats_exec_sql(): Expect the caller to always provide a transaction.
Remove some redundant assertions. The caller must hold dict_sys->mutex,
but holding dict_operation_lock is only necessary for accessing
data dictionary tables, which we are not accessing.
dict_stats_save_index_stat(): Acquire dict_sys->mutex
for invoking dict_stats_exec_sql().
dict_stats_save(), dict_stats_update_for_index(), dict_stats_update(),
dict_stats_drop_index(), dict_stats_delete_from_table_stats(),
dict_stats_delete_from_index_stats(), dict_stats_drop_table(),
dict_stats_rename_in_table_stats(), dict_stats_rename_in_index_stats(),
dict_stats_rename_table(): Use a single caller-provided
transaction that is started and committed or rolled back by the caller.
dict_stats_process_entry_from_recalc_pool(): Let the caller provide
a transaction object.
ha_innobase::open(): Pass a transaction to dict_stats_init().
ha_innobase::create(), ha_innobase::discard_or_import_tablespace():
Pass a transaction to dict_stats_update().
ha_innobase::rename_table(): Pass a transaction to
dict_stats_rename_table(). We do not use the same transaction
as the one that updated the data dictionary tables, because
we already released the dict_operation_lock. (FIXME: there is
a race condition; a lock wait on SYS_* tables could occur
in another DDL transaction until the data dictionary transaction
is committed.)
ha_innobase::info_low(): Pass a transaction to dict_stats_update()
when calculating persistent statistics.
alter_stats_norebuild(), alter_stats_rebuild(): Update the
persistent statistics as well. In this way, a single transaction
will be used for updating the statistics of a whole table, even
for partitioned tables.
ha_innobase::commit_inplace_alter_table(): Drop statistics for
all partitions when adding or dropping virtual columns, so that
the statistics will be recalculated on the next handler::open().
This is a refactored version of Oracle Bug#22469660 fix.
RecLock::add_to_waitq(), lock_table_enqueue_waiting():
Do not allow a lock wait to occur for updating statistics
in a data dictionary transaction, such as DROP TABLE. Instead,
return the previously unused error code DB_QUE_THR_SUSPENDED.
row_merge_lock_table(), row_mysql_lock_table(): Remove dead code
for handling DB_QUE_THR_SUSPENDED.
row_drop_table_for_mysql(), row_truncate_table_for_mysql():
Drop the statistics as part of the data dictionary transaction.
After TRUNCATE TABLE, the statistics will be recalculated on
subsequent ha_innobase::open(), similar to how the logic after
the above-mentioned Oracle Bug#22469660 fix in
ha_innobase::commit_inplace_alter_table() works.
btr_defragment_thread(): Use a single transaction object for
updating defragmentation statistics.
dict_stats_save_defrag_stats(), dict_stats_save_defrag_stats(),
dict_stats_process_entry_from_defrag_pool(),
dict_defrag_process_entries_from_defrag_pool(),
dict_stats_save_defrag_summary(), dict_stats_save_defrag_stats():
Add a parameter for the transaction.
dict_stats_empty_table(): Make public. This will be called by
row_truncate_table_for_mysql() after dropping persistent statistics,
to clear the memory-based statistics as well.
Define my_thread_id as an unsigned type, to avoid mismatch with
ulonglong. Change some parameters to this type.
Use size_t in a few more places.
Declare many flag constants as unsigned to avoid sign mismatch
when shifting bits or applying the unary ~ operator.
When applying the unary ~ operator to enum constants, explictly
cast the result to an unsigned type, because enum constants can
be treated as signed.
In InnoDB, change the source code line number parameters from
ulint to unsigned type. Also, make some InnoDB functions return
a narrower type (unsigned or uint32_t instead of ulint;
bool instead of ibool).
WL#7682 in MySQL 5.7 introduced the possibility to create light-weight
temporary tables in InnoDB. These are called 'intrinsic temporary tables'
in InnoDB, and in MySQL 5.7, they can be created by the optimizer for
sorting or buffering data in query processing.
In MariaDB 10.2, the optimizer temporary tables cannot be created in
InnoDB, so we should remove the dead code and related data structures.
Contains also
MDEV-10547: Test multi_update_innodb fails with InnoDB 5.7
The failure happened because 5.7 has changed the signature of
the bool handler::primary_key_is_clustered() const
virtual function ("const" was added). InnoDB was using the old
signature which caused the function not to be used.
MDEV-10550: Parallel replication lock waits/deadlock handling does not work with InnoDB 5.7
Fixed mutexing problem on lock_trx_handle_wait. Note that
rpl_parallel and rpl_optimistic_parallel tests still
fail.
MDEV-10156 : Group commit tests fail on 10.2 InnoDB (branch bb-10.2-jan)
Reason: incorrect merge
MDEV-10550: Parallel replication can't sync with master in InnoDB 5.7 (branch bb-10.2-jan)
Reason: incorrect merge
Update InnoDB to 5.6.14
Apply MySQL-5.6 hack for MySQL Bug#16434374
Move Aria-only HA_RTREE_INDEX from my_base.h to maria_def.h (breaks an assert in InnoDB)
Fix InnoDB memory leak
