Revert following bug fix:
Bug#20685029: SLAVE IO THREAD SHOULD STOP WHEN DISK IS
FULL
Bug#21753696: MAKE SHOW SLAVE STATUS NON BLOCKING IF IO
THREAD WAITS FOR DISK SPACE
This fix results in a deadlock between slave IO thread
and SQL thread.
(cherry picked from commit e3fea6c6dbb36c6ab21c4ab777224560e9608b53)
FULL
Bug#21753696: MAKE SHOW SLAVE STATUS NON BLOCKING IF IO
THREAD WAITS FOR DISK SPACE
Problem:
========
Currently SHOW SLAVE STATUS blocks if IO thread waits for
disk space. This makes automation tools verifying
server health block on taking relevant action. Finally this
will create SHOW SLAVE STATUS piles.
Analysis:
=========
SHOW SLAVE STATUS hangs on mi->data_lock if relay log write
is waiting for free disk space while holding mi->data_lock.
mi->data_lock is needed to protect the format description
event (mi->format_description_event) which is accessed by
the clients running FLUSH LOGS and slave IO thread. Note
relay log writes don't need to be protected by
mi->data_lock, LOCK_log is used to protect relay log between
IO and SQL thread (see MYSQL_BIN_LOG::append_event). The
code takes mi->data_lock to protect
mi->format_description_event during relay log rotate which
might get triggered right after relay log write.
Fix:
====
Release the data_lock just for the duration of writing into
relay log.
Made change to ensure the following lock order is maintained
to avoid deadlocks.
data_lock, LOCK_log
data_lock is held during relay log rotations to protect
the description event.
Description: The command FLUSH DES_KEY_FILE is expected to
reload the DES keys from the file that was specified with
the "--des-key-file" option at server startup. But it is not
behaving as expected.
Analysis: The des file reload is defined within a wrong
conditional directive, rendering the command ineffective.
Macro "OPENSSL" was used instead of "HAVE_OPENSSL" macro.
Fix: "OPENSSL" macro is changed to "HAVE_OPENSSL".
Changed HA_EXTRA_NORMAL to HA_EXTRA_NOT_USED (more clean)
mysql-test/suite/maria/lock.result:
More extensive tests of LOCK TABLE with FLUSH and REPAIR
mysql-test/suite/maria/lock.test:
More extensive tests of LOCK TABLE with FLUSH and REPAIR
sql/sql_admin.cc:
Fix that REPAIR TABLE ... USE_FRM works with LOCK TABLES
sql/sql_base.cc:
Ensure that transactions are closed in ARIA when doing flush
HA_EXTRA_NORMAL -> HA_EXTRA_NOT_USED
Don't call extra many times for a table in close_all_tables_for_name()
Added test if table_list->table as this can happen in error situations
sql/sql_partition.cc:
HA_EXTRA_NORMAL -> HA_EXTRA_NOT_USED
sql/sql_reload.cc:
Fixed comment
sql/sql_table.cc:
HA_EXTRA_NORMAL -> HA_EXTRA_NOT_USED
sql/sql_trigger.cc:
HA_EXTRA_NORMAL -> HA_EXTRA_NOT_USED
sql/sql_truncate.cc:
HA_EXTRA_FORCE_REOPEN -> HA_EXTRA_PREPARE_FOR_DROP for truncate, as this speeds up truncate by not having to flush the cache to disk.
The bug case is similar to one fixed earlier bug_49536.
Deadlock involving LOCK_log appears to be possible because the purge running thread
is holding LOCK_log whereas there is no sense of doing that and which fact was
exploited by the earlier bug fixes.
Fixed with small reengineering of rotate_and_purge(), adding two new methods and
setting up a policy to execute those instead of the former
rotate_and_purge(RP_LOCK_LOG_IS_ALREADY_LOCKED).
The policy for using rotate(), purge() is that if the caller acquires LOCK_log itself,
it should call rotate(), release the mutex and run purge().
Side effect of this patch is refining error message of bug@11747416 to print
the whole path.
mysql-test/suite/rpl/r/rpl_cant_read_event_incident.result:
the file name printing is changed to a relative path instead of just the file name.
mysql-test/suite/rpl/r/rpl_log_pos.result:
the file name printing is changed to a relative path instead of just the file name.
mysql-test/suite/rpl/r/rpl_manual_change_index_file.result:
the file name printing is changed to a relative path instead of just the file name.
mysql-test/suite/rpl/r/rpl_packet.result:
the file name printing is changed to a relative path instead of just the file name.
mysql-test/suite/rpl/r/rpl_rotate_purge_deadlock.result:
new result file is added.
mysql-test/suite/rpl/t/rpl_cant_read_event_incident.test:
The test of that bug can't satisfy windows and unix backslash interpretation so windows
execution is chosen to bypass.
mysql-test/suite/rpl/t/rpl_rotate_purge_deadlock-master.opt:
new opt file is added.
mysql-test/suite/rpl/t/rpl_rotate_purge_deadlock.test:
regression test is added as well as verification of a
possible side effect of the fixes is tried.
sql/log.cc:
LOCK_log is never taken during execution of log purging routine.
The former MYSQL_BIN_LOG::rotate_and_purge is made to necessarily
acquiring and releasing LOCK_log.
If caller takes the mutex itself it has to use a new rotate(), purge()
methods combination and to never let purge() be run with LOCK_log grabbed.
split apart to allow
the caller to chose either it
Simulation of concurrently rotating/purging threads is added.
sql/log.h:
new rotate(), purge() methods are added to be used instead of
the former rotate_and_purge(RP_LOCK_LOG_IS_ALREADY_LOCKED).
rotate_and_purge() signature is changed. Caller should not call rotate_and_purge()
but rather {rotate(), purge()} if LOCK_log is acquired by it.
sql/rpl_injector.cc:
changes to reflect the new rotate_and_purge() signature.
sql/sql_class.h:
unnecessary constants are removed.
sql/sql_parse.cc:
changes to reflect the new rotate_and_purge() signature.
sql/sql_reload.cc:
changes to reflect the new rotate_and_purge() signature.
sql/sql_repl.cc:
followup for bug@11747416: the file name printing is changed to a relative
path instead of just the file name.
The bug case is similar to one fixed earlier bug_49536.
Deadlock involving LOCK_log appears to be possible because the purge running thread
is holding LOCK_log whereas there is no sense of doing that and which fact was
exploited by the earlier bug fixes.
Fixed with small reengineering of rotate_and_purge(), adding two new methods and
setting up a policy to execute those instead of the former
rotate_and_purge(RP_LOCK_LOG_IS_ALREADY_LOCKED).
The policy for using rotate(), purge() is that if the caller acquires LOCK_log itself,
it should call rotate(), release the mutex and run purge().
Side effect of this patch is refining error message of bug@11747416 to print
the whole path.
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
FLUSH TABLES under FLUSH TABLES <list> WITH READ LOCK leads
to assert failure.
This assert was triggered if a statement tried up upgrade a metadata
lock with an active FLUSH TABLE <list> WITH READ LOCK. The assert
checks that the connection already holds a global intention exclusive
metadata lock. However, FLUSH TABLE <list> WITH READ LOCK does not
acquire this lock in order to be compatible with FLUSH TABLES WITH
READ LOCK. Therefore any metadata lock upgrade caused the assert to
be triggered.
This patch fixes the problem by preventing metadata lock upgrade
if the connection has an active FLUSH TABLE <list> WITH READ LOCK.
ER_TABLE_NOT_LOCKED_FOR_WRITE will instead be reported to the client.
Test case added to flush.test.
FLUSH TABLES under FLUSH TABLES <list> WITH READ LOCK leads
to assert failure.
This assert was triggered if a statement tried up upgrade a metadata
lock with an active FLUSH TABLE <list> WITH READ LOCK. The assert
checks that the connection already holds a global intention exclusive
metadata lock. However, FLUSH TABLE <list> WITH READ LOCK does not
acquire this lock in order to be compatible with FLUSH TABLES WITH
READ LOCK. Therefore any metadata lock upgrade caused the assert to
be triggered.
This patch fixes the problem by preventing metadata lock upgrade
if the connection has an active FLUSH TABLE <list> WITH READ LOCK.
ER_TABLE_NOT_LOCKED_FOR_WRITE will instead be reported to the client.
Test case added to flush.test.
Manual merge from mysql-5.1-bugteam into mysql-5.5-bugteam.
Conflicts
=========
Text conflict in sql/log.cc
Text conflict in sql/log.h
Text conflict in sql/slave.cc
Text conflict in sql/sql_parse.cc
Text conflict in sql/sql_priv.h
Manual merge from mysql-5.1-bugteam into mysql-5.5-bugteam.
Conflicts
=========
Text conflict in sql/log.cc
Text conflict in sql/log.h
Text conflict in sql/slave.cc
Text conflict in sql/sql_parse.cc
Text conflict in sql/sql_priv.h
table causes assert failure".
Attempting to use FLUSH TABLE table_list WITH READ LOCK
statement for a MERGE table led to an assertion failure if
one of its children was not present in the list of tables
to be flushed. The problem was not visible in non-debug builds.
The assertion failure was caused by the fact that in such
situations FLUSH TABLES table_list WITH READ LOCK implementation
tried to use (e.g. lock) such child tables without acquiring
metadata lock on them. This happened because when opening tables
we assumed metadata locks on all tables were already acquired
earlier during statement execution and a such assumption was
false for MERGE children.
This patch fixes the problem by ensuring at open_tables() time
that we try to acquire metadata locks on all tables to be opened.
For normal tables such requests are satisfied instantly since
locks are already acquired for them. For MERGE children metadata
locks are acquired in normal fashion.
Note that FLUSH TABLES merge_table WITH READ LOCK will lock for
read both the MERGE table and its children but will flush only
the MERGE table. To flush children one has to mention them in table
list explicitly. This is expected behavior and it is consistent with
usage patterns for this statement (e.g. in mysqlhotcopy script).
mysql-test/r/flush.result:
Added test case for bug #55273 "FLUSH TABLE tm WITH READ LOCK
for Merge table causes assert failure".
mysql-test/t/flush.test:
Added test case for bug #55273 "FLUSH TABLE tm WITH READ LOCK
for Merge table causes assert failure".
sql/sql_base.cc:
Changed lock_table_names() to support newly introduced
MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK flag.
sql/sql_base.h:
Introduced MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK flag for
open_tables() and lock_table_names() which allows to skip
acquiring of global and schema-scope locks when SNW, SNRW or
X metadata locks are acquired.
sql/sql_reload.cc:
Changed "FLUSH TABLES table_list WITH READ LOCK" code not to
cause assert about missing metadata locks when MERGE table is
flushed without one of its underlying tables.
To achieve this we no longer call open_and_lock_tables() with
MYSQL_OPEN_HAS_MDL_LOCK flag so this function automatically
acquires metadata locks on MERGE children if such lock has
not been already acquired at earlier stage. Instead we call
this function with MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK flag to
suppress acquiring of global IX lock in order to keep FLUSH
TABLES table_list WITH READ LOCK compatible with FLUSH TABLE
WITH READ LOCK.
Also changed implementation to use lock_table_names() function
for pre-acquiring of metadata locks instead of custom code.
To implement this change moved setting of open_type member for
table list elements to parser.
sql/sql_yacc.yy:
Now we set acceptable type of table for FLUSH TABLES table_list
WITH READ LOCK at parsing time instead of execution time.
table causes assert failure".
Attempting to use FLUSH TABLE table_list WITH READ LOCK
statement for a MERGE table led to an assertion failure if
one of its children was not present in the list of tables
to be flushed. The problem was not visible in non-debug builds.
The assertion failure was caused by the fact that in such
situations FLUSH TABLES table_list WITH READ LOCK implementation
tried to use (e.g. lock) such child tables without acquiring
metadata lock on them. This happened because when opening tables
we assumed metadata locks on all tables were already acquired
earlier during statement execution and a such assumption was
false for MERGE children.
This patch fixes the problem by ensuring at open_tables() time
that we try to acquire metadata locks on all tables to be opened.
For normal tables such requests are satisfied instantly since
locks are already acquired for them. For MERGE children metadata
locks are acquired in normal fashion.
Note that FLUSH TABLES merge_table WITH READ LOCK will lock for
read both the MERGE table and its children but will flush only
the MERGE table. To flush children one has to mention them in table
list explicitly. This is expected behavior and it is consistent with
usage patterns for this statement (e.g. in mysqlhotcopy script).
