handle_segfault is the signal handler code of mysqld. however, it makes
calls to potentially unsafe functions localtime_r, fprintf, fflush.
include/my_stacktrace.h:
Add safe versions of itoa() write() and snprintf().
libmysqld/CMakeLists.txt:
Move signal handler to separate file.
mysys/stacktrace.c:
Remove unsafe function calls.
sql/CMakeLists.txt:
Move signal handler to separate file.
sql/mysqld.cc:
Move signal handler to separate file.
sql/set_var.h:
Add missing #include dependency.
sql/sys_vars.cc:
Cleanup .h and .cc files.
sql/sys_vars.h:
Cleanup .h and .cc files.
BY CACHING OR REDUCING CREATEEVENT CALLS".
5.5 versions of MySQL server performed worse than 5.1 versions
under single-connection workload in autocommit mode on Windows XP.
Part of this slowdown can be attributed to overhead associated
with constant creation/destruction of MDL_lock objects in the MDL
subsystem. The problem is that creation/destruction of these
objects causes creation and destruction of associated
synchronization primitives, which are expensive on Windows XP.
This patch tries to alleviate this problem by introducing a cache
of unused MDL_object_lock objects. Instead of destroying such
objects we put them into the cache and then reuse with a new
key when creation of a new object is requested.
To limit the size of this cache, a new --metadata-locks-cache-size
start-up parameter was introduced.
mysql-test/r/mysqld--help-notwin.result:
Updated test after adding --metadata-locks-cache-size
parameter.
mysql-test/r/mysqld--help-win.result:
Updated test after adding --metadata-locks-cache-size
parameter.
mysql-test/suite/sys_vars/r/metadata_locks_cache_size_basic.result:
Added test coverage for newly introduced --metadata_locks_cache_size
start-up parameter and corresponding global read-only variable.
mysql-test/suite/sys_vars/t/metadata_locks_cache_size_basic-master.opt:
Added test coverage for newly introduced --metadata_locks_cache_size
start-up parameter and corresponding global read-only variable.
mysql-test/suite/sys_vars/t/metadata_locks_cache_size_basic.test:
Added test coverage for newly introduced --metadata_locks_cache_size
start-up parameter and corresponding global read-only variable.
sql/mdl.cc:
Introduced caching of unused MDL_object_lock objects, in order to
avoid costs associated with constant creation and destruction of
such objects in single-connection workloads run in autocommit mode.
Such costs can be pretty high on systems where creation and
destruction of synchronization primitives require a system call
(e.g. Windows XP).
To implement this cache,a list of unused MDL_object_lock instances
was added to MDL_map object. Instead of being destroyed
MDL_object_lock instances are put into this list and re-used later
when creation of a new instance is required. Also added
MDL_lock::m_version counter to allow threads having outstanding
references to an MDL_object_lock instance to notice that it has
been moved to the unused objects list.
Added a global variable for a start-up parameter that limits
the size of the unused objects list.
Note that we don't cache MDL_scoped_lock objects since they
are supposed to be created only during execution of DDL
statements and therefore should not affect performance much.
sql/mdl.h:
Added a global variable for start-up parameter that limits the
size of the unused MDL_object_lock objects list and constant
for its default value.
sql/sql_plist.h:
Added I_P_List<>::pop_front() function.
sql/sys_vars.cc:
Introduced --metadata-locks-cache-size start-up parameter
for specifying size of the cache of unused MDL_object_lock
objects.
BY CACHING OR REDUCING CREATEEVENT CALLS".
5.5 versions of MySQL server performed worse than 5.1 versions
under single-connection workload in autocommit mode on Windows XP.
Part of this slowdown can be attributed to overhead associated
with constant creation/destruction of MDL_lock objects in the MDL
subsystem. The problem is that creation/destruction of these
objects causes creation and destruction of associated
synchronization primitives, which are expensive on Windows XP.
This patch tries to alleviate this problem by introducing a cache
of unused MDL_object_lock objects. Instead of destroying such
objects we put them into the cache and then reuse with a new
key when creation of a new object is requested.
To limit the size of this cache, a new --metadata-locks-cache-size
start-up parameter was introduced.
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
of service in prepared statements).
sql/sql_prepare.cc:
At mysql_stmt_get_longdata(): instead of pushing an internal
error handler (as done in 5.1-tree) we save, set and restore
the statement's diagnostics area and warning info.
After the WL#2687, the binlog_cache_size and max_binlog_cache_size affect both the
stmt-cache and the trx-cache. This means that the resource used is twice the amount
expected/defined by the user.
The binlog_cache_use is incremented when the stmt-cache or the trx-cache is used
and binlog_cache_disk_use is incremented when the disk space from the stmt-cache or the
trx-cache is used. This behavior does not allow to distinguish which cache may be harming
performance due to the extra disk accesses and needs to have its in-memory cache
increased.
To fix the problem, we introduced two new options and status variables related to the
stmt-cache:
Options:
. binlog_stmt_cache_size
. max_binlog_stmt_cache_size
Status Variables:
. binlog_stmt_cache_use
. binlog_stmt_cache_disk_use
So there are
. binlog_cache_size that defines the size of the transactional cache for
updates to transactional engines for the binary log.
. binlog_stmt_cache_size that defines the size of the statement cache for
updates to non-transactional engines for the binary log.
. max_binlog_cache_size that sets the total size of the transactional
cache.
. max_binlog_stmt_cache_size that sets the total size of the statement
cache.
. binlog_cache_use that identifies the number of transactions that used the
temporary transactional binary log cache.
. binlog_cache_disk_use that identifies the number of transactions that used
the temporary transactional binary log cache but that exceeded the value of
binlog_cache_size.
. binlog_stmt_cache_use that identifies the number of statements that used the
temporary non-transactional binary log cache.
. binlog_stmt_cache_disk_use that identifies the number of statements that used
the temporary non-transactional binary log cache but that exceeded the value of
binlog_stmt_cache_size.
include/my_sys.h:
Updated message on disk_writes' usage.
mysql-test/extra/binlog_tests/binlog_cache_stat.test:
Updated the test case and added code to check the new status variables
binlog_stmt_cache_use and binlog_stmt_cache_disk_use.
mysql-test/extra/rpl_tests/rpl_binlog_max_cache_size.test:
Updated the test case to use the new system variables max_binlog_stmt_cache_size and binlog_stmt_cache_size.
mysql-test/r/mysqld--help-notwin.result:
Updated the result file.
mysql-test/suite/binlog/r/binlog_mixed_cache_stat.result:
Updated the result file.
mysql-test/suite/binlog/r/binlog_row_cache_stat.result:
Updated the result file.
mysql-test/suite/binlog/r/binlog_stm_cache_stat.result:
Updated the result file.
mysql-test/suite/rpl/r/rpl_mixed_binlog_max_cache_size.result:
Update the result file.
mysql-test/suite/rpl/r/rpl_row_binlog_max_cache_size.result:
Update the result file.
mysql-test/suite/rpl/r/rpl_stm_binlog_max_cache_size.result:
Updated the result file.
mysql-test/suite/sys_vars/inc/binlog_stmt_cache_size_basic.inc:
Added a test case to check the binlog_stmt_cache_size.
mysql-test/suite/sys_vars/r/binlog_stmt_cache_size_basic_32.result:
Updated the result file.
mysql-test/suite/sys_vars/r/binlog_stmt_cache_size_basic_64.result:
Updated the result file.
mysql-test/suite/sys_vars/r/max_binlog_stmt_cache_size_basic.result:
Updated the result file.
mysql-test/suite/sys_vars/t/binlog_stmt_cache_size_basic_32.test:
Added a test case to check the binlog_stmt_cache_size.
mysql-test/suite/sys_vars/t/binlog_stmt_cache_size_basic_64.test:
Added a test case to check the binlog_stmt_cache_size.
mysql-test/suite/sys_vars/t/max_binlog_cache_size_func-master.opt:
Removed because there is no test case max_binlog_cache_size_func.
mysql-test/suite/sys_vars/t/max_binlog_stmt_cache_size_basic.test:
Added a test case to check the system variable max_binlog_stmt_cache_size.
sql/log.cc:
There two main changes in here:
. Changed the set_write_error() as an error message is set according
to the type of the cache.
. Created the function set_binlog_cache_info where references to the
appropriate status and system variables are set and the server can
smoothly compute statistics and set the maximum size for each cache.
sql/log.h:
Changed the signature of the function in order to identify the error message
to be printed out as there is a different error code for each type of cache.
sql/mysqld.cc:
Added new status variables binlog_stmt_cache_use and binlog_stmt_cache_disk_use.
sql/mysqld.h:
Added new system variables max_binlog_stmt_cache_size and binlog_stmt_cache_size.
sql/share/errmsg-utf8.txt:
Added new error message related to the statement cache.
sql/sys_vars.cc:
Added new system variables max_binlog_stmt_cache_size and binlog_stmt_cache_size.
After the WL#2687, the binlog_cache_size and max_binlog_cache_size affect both the
stmt-cache and the trx-cache. This means that the resource used is twice the amount
expected/defined by the user.
The binlog_cache_use is incremented when the stmt-cache or the trx-cache is used
and binlog_cache_disk_use is incremented when the disk space from the stmt-cache or the
trx-cache is used. This behavior does not allow to distinguish which cache may be harming
performance due to the extra disk accesses and needs to have its in-memory cache
increased.
To fix the problem, we introduced two new options and status variables related to the
stmt-cache:
Options:
. binlog_stmt_cache_size
. max_binlog_stmt_cache_size
Status Variables:
. binlog_stmt_cache_use
. binlog_stmt_cache_disk_use
So there are
. binlog_cache_size that defines the size of the transactional cache for
updates to transactional engines for the binary log.
. binlog_stmt_cache_size that defines the size of the statement cache for
updates to non-transactional engines for the binary log.
. max_binlog_cache_size that sets the total size of the transactional
cache.
. max_binlog_stmt_cache_size that sets the total size of the statement
cache.
. binlog_cache_use that identifies the number of transactions that used the
temporary transactional binary log cache.
. binlog_cache_disk_use that identifies the number of transactions that used
the temporary transactional binary log cache but that exceeded the value of
binlog_cache_size.
. binlog_stmt_cache_use that identifies the number of statements that used the
temporary non-transactional binary log cache.
. binlog_stmt_cache_disk_use that identifies the number of statements that used
the temporary non-transactional binary log cache but that exceeded the value of
binlog_stmt_cache_size.
The server contained code for the server variable and
option thread_pool_size, but this server variable where
not used anywhere.
The variable is probably remains from backporting too
much from 6.0 (specifically, the thread pool
implementation was not backported from 6.0, which this
variable is associated with).
This patch eliminates the variable from the server.
The server contained code for the server variable and
option thread_pool_size, but this server variable where
not used anywhere.
The variable is probably remains from backporting too
much from 6.0 (specifically, the thread pool
implementation was not backported from 6.0, which this
variable is associated with).
This patch eliminates the variable from the server.
The error message for ER_SLAVE_HEARTBEAT_VALUE_OUT_OF_RANGE was
hard coded. Additionally, the same error was used in three
separate error symptoms: 1. when heartbeat period exceeds the
value of slave_net_timeout, 2. when it is smaller than 1
milisecond and 3. when it was not in range, ie, either negative
or greater than the maximum allowed.
We fix this by splitting into three distinct errors and by
removing the message from the source code and moving it to the
errmsg-utf8.txt file.
The error message for ER_SLAVE_HEARTBEAT_VALUE_OUT_OF_RANGE was
hard coded. Additionally, the same error was used in three
separate error symptoms: 1. when heartbeat period exceeds the
value of slave_net_timeout, 2. when it is smaller than 1
milisecond and 3. when it was not in range, ie, either negative
or greater than the maximum allowed.
We fix this by splitting into three distinct errors and by
removing the message from the source code and moving it to the
errmsg-utf8.txt file.
Before this fix, some tests failed due to lack of instrumentation slots
in the performance schema, because the default sizing was too low.
Now that more code has been instrumented, the default sizing has to be adjusted
to match the current instrumentation consumption.
This change:
- increases the number of rwlock classes from 20 to 30,
- increases the number of rwlock and mutex instances to 1 million.
Both are to account for the volume of data instrumented
when the innodb storage engine is used (because of the innodb buffer pool).
Adjusted the test output accordingly.
Before this fix, some tests failed due to lack of instrumentation slots
in the performance schema, because the default sizing was too low.
Now that more code has been instrumented, the default sizing has to be adjusted
to match the current instrumentation consumption.
This change:
- increases the number of rwlock classes from 20 to 30,
- increases the number of rwlock and mutex instances to 1 million.
Both are to account for the volume of data instrumented
when the innodb storage engine is used (because of the innodb buffer pool).
Adjusted the test output accordingly.
example files)
The system variable 'thread_concurrency' has been
(re-)enabled on all platforms, to prevent startup
errors.
'thread_concurrency' is unused and has no effect,
on any platform, in MySQL 5.1 and later versions. It
will be deprecated, and removed, in context of
worklog WL#5265
mysql-test/include/have_thread_concurrency.inc:
include/have_thread_concurrency.inc was only needed
to support platforms that didn't have the
thread_concurrency variable available. Since the
variable is now available on all platforms, the file
is removed.
example files)
The system variable 'thread_concurrency' has been
(re-)enabled on all platforms, to prevent startup
errors.
'thread_concurrency' is unused and has no effect,
on any platform, in MySQL 5.1 and later versions. It
will be deprecated, and removed, in context of
worklog WL#5265
