bzr merge lp:maria/5.5
...
Text conflict in CMakeLists.txt
Text conflict in sql/mysqld.cc
Text conflict in sql/sql_class.h
Text conflict in sql/sql_truncate.cc
4 conflicts encountered.
two tests still fail:
main.innodb_icp and main.range_vs_index_merge_innodb
call records_in_range() with both range ends being open
(which triggers an assert)
PROBLEM:
mysql provides a feature where in a session which is
idle for a period specified by the wait_timeout variable
(whose value is in seconds), the session is closed
This feature is not present when we use thread pool.
FIX:
This patch implements the interface functions which is
required to implement the wait_timeout functionality
in the thread pool plugin.
PROBLEM:
mysql provides a feature where in a session which is
idle for a period specified by the wait_timeout variable
(whose value is in seconds), the session is closed
This feature is not present when we use thread pool.
FIX:
This patch implements the interface functions which is
required to implement the wait_timeout functionality
in the thread pool plugin.
KEY UPDATES WITH A LIMIT OF 1
Problem: The unsafety warning for statements such as
update...limit1 where pk=1 are thrown when binlog-format
= STATEMENT,despite of the fact that such statements are
actually safe. this leads to filling up of the disk space
with false warnings.
Solution: This is not a complete fix for the problem, but
prevents the disks from getting filled up. This should
therefore be regarded as a workaround. In the future this
should be overriden by server general suppress/filtering
framework. It should also be noted that another worklog is
supposed to defeat this case's artificial unsafety.
We use a warning suppression mechanism to detect warning flood,
enable the suppression, and disable this when the average
warnings/second has reduced to acceptable limits.
Activation: The supression for LIMIT unsafe statements are
activated when the last 50 warnings were logged in less
than 50 seconds.
Supression: Once activated this supression will prevent the
individual warnings to be logged in the error log, but print
the warning for every 50 warnings with the note:
"The last warning was repeated N times in last S seconds"
Noteworthy is the fact that this supression works only on the
error logs and the warnings seen by the clients will remain as
it is (i.e. one warning/ unsafe statement)
Deactivation: The supression will be deactivated once the
average # of warnings/sec have gone down to the acceptable limits.
sql/sql_class.cc:
Added code to supress warning while logging them to error-log.
KEY UPDATES WITH A LIMIT OF 1
Problem: The unsafety warning for statements such as
update...limit1 where pk=1 are thrown when binlog-format
= STATEMENT,despite of the fact that such statements are
actually safe. this leads to filling up of the disk space
with false warnings.
Solution: This is not a complete fix for the problem, but
prevents the disks from getting filled up. This should
therefore be regarded as a workaround. In the future this
should be overriden by server general suppress/filtering
framework. It should also be noted that another worklog is
supposed to defeat this case's artificial unsafety.
We use a warning suppression mechanism to detect warning flood,
enable the suppression, and disable this when the average
warnings/second has reduced to acceptable limits.
Activation: The supression for LIMIT unsafe statements are
activated when the last 50 warnings were logged in less
than 50 seconds.
Supression: Once activated this supression will prevent the
individual warnings to be logged in the error log, but print
the warning for every 50 warnings with the note:
"The last warning was repeated N times in last S seconds"
Noteworthy is the fact that this supression works only on the
error logs and the warnings seen by the clients will remain as
it is (i.e. one warning/ unsafe statement)
Deactivation: The supression will be deactivated once the
average # of warnings/sec have gone down to the acceptable limits.
- Add Monty Program Ab copyright in new files
- Change Apc_target::make_apc_call() to accept a C++-style
functor (instead of C-style function + parameter)
Merged latest MariaDB development in: bzr merge lp:maria/5.5
=>
Text conflict in CMakeLists.txt
Text conflict in sql/handler.h
Text conflict in support-files/CMakeLists.txt
3 conflicts
- Make SHOW EXPLAIN code take into account that st_select_lex object without joins can be
a full-featured SELECTs which were already executed and cleaned up.
Analysis:
-------------
If server is started with limit of MAX_CONNECTIONS and
MAX_USER_CONNECTIONS then only MAX_USER_CONNECTIONS of any particular
users can be connected to server and total MAX_CONNECTIONS of client can
be connected to server.
Server maintains a counter for total CONNECTIONS and total CONNECTIONS
from particular user.
Here, MAX_CONNECTIONS of connections are created to server. Out of this
MAX_CONNECTIONS, connections from particular user (say USER1) are
also created. The connections from USER1 is lesser than
MAX_USER_CONNECTIONS. After that there was one more connection request from
USER1. Since USER1 can still create connections as he havent reached
MAX_USER_CONNECTIONS, server increments counter of CONNECTIONS per user.
As server already has MAX_CONNECTIONS of connections, next check to total
CONNECTION count fails. In this case control is returned WITHOUT
decrementing the CONNECTIONS per user. So the counter per user CONNECTIONS goes
on incrementing for each attempt until current connections are closed.
And because of this counter per CONNECTIONS reached MAX_USER_CONNECTIONS.
So, next connections form USER1 user always returns with MAX_USER_CONNECTION
limit error, even when total connection to sever are less than MAX_CONNECTIONS.
Fix:
-------------
This issue is occurred because of not handling counters properly in the
server. Changed the code to handle per user connection counters properly.
Analysis:
-------------
If server is started with limit of MAX_CONNECTIONS and
MAX_USER_CONNECTIONS then only MAX_USER_CONNECTIONS of any particular
users can be connected to server and total MAX_CONNECTIONS of client can
be connected to server.
Server maintains a counter for total CONNECTIONS and total CONNECTIONS
from particular user.
Here, MAX_CONNECTIONS of connections are created to server. Out of this
MAX_CONNECTIONS, connections from particular user (say USER1) are
also created. The connections from USER1 is lesser than
MAX_USER_CONNECTIONS. After that there was one more connection request from
USER1. Since USER1 can still create connections as he havent reached
MAX_USER_CONNECTIONS, server increments counter of CONNECTIONS per user.
As server already has MAX_CONNECTIONS of connections, next check to total
CONNECTION count fails. In this case control is returned WITHOUT
decrementing the CONNECTIONS per user. So the counter per user CONNECTIONS goes
on incrementing for each attempt until current connections are closed.
And because of this counter per CONNECTIONS reached MAX_USER_CONNECTIONS.
So, next connections form USER1 user always returns with MAX_USER_CONNECTION
limit error, even when total connection to sever are less than MAX_CONNECTIONS.
Fix:
-------------
This issue is occurred because of not handling counters properly in the
server. Changed the code to handle per user connection counters properly.
PROBLEM:
Threads end-up in deadlock due to locks acquired as described
below,
con1: Run Query on a table.
It is important that this SELECT must back-off while
trying to open the t1 and enter into wait_for_condition().
The SELECT then is blocked trying to lock mysys_var->mutex
which is held by con3. The very significant fact here is
that mysys_var->current_mutex will still point to LOCK_open,
even if LOCK_open is no longer held by con1 at this point.
con2: Try dropping table used in con1 or query some table.
It will hold LOCK_open and be blocked trying to lock
kernel_mutex held by con4.
con3: Try killing the query run by con1.
It will hold THD::LOCK_thd_data belonging to con1 while
trying to lock mysys_var->current_mutex belonging to con1.
But current_mutex will point to LOCK_open which is held
by con2.
con4: Get innodb engine status
It will hold kernel_mutex, trying to lock THD::LOCK_thd_data
belonging to con1 which is held by con3.
So while technically only con2, con3 and con4 participate in the
deadlock, con1's mysys_var->current_mutex pointing to LOCK_open
is a vital component of the deadlock.
CYCLE = (THD::LOCK_thd_data -> LOCK_open ->
kernel_mutex -> THD::LOCK_thd_data)
FIX:
LOCK_thd_data has responsibility of protecting,
1) thd->query, thd->query_length
2) VIO
3) thd->mysys_var (used by KILL statement and shutdown)
4) THD during thread delete.
Among above responsibilities, 1), 2)and (3,4) seems to be three
independent group of responsibility. If there is different LOCK
owning responsibility of (3,4), the above mentioned deadlock cycle
can be avoid. This fix introduces LOCK_thd_kill to handle
responsibility (3,4), which eliminates the deadlock issue.
Note: The problem is not found in 5.5. Introduction MDL subsystem
caused metadata locking responsibility to be moved from TDC/TC to
MDL subsystem. Due to this, responsibility of LOCK_open is reduced.
As the use of LOCK_open is removed in open_table() and
mysql_rm_table() the above mentioned CYCLE does not form.
Revision ID for changes,
open_table() = dlenev@mysql.com-20100727133458-m3ua9oslnx8fbbvz
mysql_rm_table() = jon.hauglid@oracle.com-20101116100012-kxep9txz2fxy3nmw
PROBLEM:
Threads end-up in deadlock due to locks acquired as described
below,
con1: Run Query on a table.
It is important that this SELECT must back-off while
trying to open the t1 and enter into wait_for_condition().
The SELECT then is blocked trying to lock mysys_var->mutex
which is held by con3. The very significant fact here is
that mysys_var->current_mutex will still point to LOCK_open,
even if LOCK_open is no longer held by con1 at this point.
con2: Try dropping table used in con1 or query some table.
It will hold LOCK_open and be blocked trying to lock
kernel_mutex held by con4.
con3: Try killing the query run by con1.
It will hold THD::LOCK_thd_data belonging to con1 while
trying to lock mysys_var->current_mutex belonging to con1.
But current_mutex will point to LOCK_open which is held
by con2.
con4: Get innodb engine status
It will hold kernel_mutex, trying to lock THD::LOCK_thd_data
belonging to con1 which is held by con3.
So while technically only con2, con3 and con4 participate in the
deadlock, con1's mysys_var->current_mutex pointing to LOCK_open
is a vital component of the deadlock.
CYCLE = (THD::LOCK_thd_data -> LOCK_open ->
kernel_mutex -> THD::LOCK_thd_data)
FIX:
LOCK_thd_data has responsibility of protecting,
1) thd->query, thd->query_length
2) VIO
3) thd->mysys_var (used by KILL statement and shutdown)
4) THD during thread delete.
Among above responsibilities, 1), 2)and (3,4) seems to be three
independent group of responsibility. If there is different LOCK
owning responsibility of (3,4), the above mentioned deadlock cycle
can be avoid. This fix introduces LOCK_thd_kill to handle
responsibility (3,4), which eliminates the deadlock issue.
Note: The problem is not found in 5.5. Introduction MDL subsystem
caused metadata locking responsibility to be moved from TDC/TC to
MDL subsystem. Due to this, responsibility of LOCK_open is reduced.
As the use of LOCK_open is removed in open_table() and
mysql_rm_table() the above mentioned CYCLE does not form.
Revision ID for changes,
open_table() = dlenev@mysql.com-20100727133458-m3ua9oslnx8fbbvz
mysql_rm_table() = jon.hauglid@oracle.com-20101116100012-kxep9txz2fxy3nmw
BUG#11761686 insert_id event is not filtered.
Two issues are covered.
INSERT into autoincrement field which is not the first part in the composed primary key
is unsafe by autoincrement logging design. The case is specific to MyISAM engine
because Innodb does not allow such table definition.
However no warnings and row-format logging in the MIXED mode was done, and
that is fixed.
Int-, Rand-, User-var log-events were not filtered along with their parent
query that made possible them to screw up execution context of the following
query.
Fixed with deferring their execution until the parent query.
******
Bug#11754117
Post review fixes.
mysql-test/suite/rpl/r/rpl_auto_increment_bug45679.result:
a new result file is added.
mysql-test/suite/rpl/r/rpl_filter_tables_not_exist.result:
results updated.
mysql-test/suite/rpl/t/rpl_auto_increment_bug45679.test:
regression test for BUG#11754117-45670 is added.
mysql-test/suite/rpl/t/rpl_filter_tables_not_exist.test:
regression test for filtering issue of BUG#11754117 - 45670 is added.
sql/log_event.cc:
Logics are added for deferring and executing events associated
with the Query event.
sql/log_event.h:
Interface to deferred events batch execution is added.
sql/rpl_rli.cc:
initialization for new RLI members is added.
sql/rpl_rli.h:
New members to RLI are added to facilitate deferred events gathering
and execution control;
two general character RLI cleanup methods are constructed.
sql/rpl_utility.cc:
Deferred_log_events methods are difined.
sql/rpl_utility.h:
A new class Deferred_log_events is defined to implement
IRU events gathering, execution and cleanup.
sql/slave.cc:
Necessary changes to initialize `rli->deferred_events' and prevent
deferred event deletion in the main read-exec branch.
sql/sql_base.cc:
A new safe-check function for multi-part pk with auto-increment is defined
and deployed in lock_tables().
sql/sql_class.cc:
Initialization for a new member and replication cleanups are added
to THD class.
sql/sql_class.h:
THD class receives a new member to hold a specific execution
context for slave applier.
sql/sql_parse.cc:
Execution of the deferred event in started prior to its parent query.
BUG#11761686 insert_id event is not filtered.
Two issues are covered.
INSERT into autoincrement field which is not the first part in the composed primary key
is unsafe by autoincrement logging design. The case is specific to MyISAM engine
because Innodb does not allow such table definition.
However no warnings and row-format logging in the MIXED mode was done, and
that is fixed.
Int-, Rand-, User-var log-events were not filtered along with their parent
query that made possible them to screw up execution context of the following
query.
Fixed with deferring their execution until the parent query.
******
Bug#11754117
Post review fixes.
