When compressed myisam files are opened, they are always memory mapped
sometimes causing memory swapping problems.
When we mmap the myisam compressed tables of size greater than the memory
available, the kswapd0 process utilization is very high consuming 30-40% of
the cpu. This happens only with linux kernels older than 2.6.9
With newer linux kernels, we don't have this problem of high cpu consumption
and this option may not be required.
The option 'myisam_mmap_size' is added to limit the amount of memory used for
memory mapping of myisam files. This option is not dynamic.
The default value on 32 bit system is 4294967295 bytes and on 64 bit system it
is 18446744073709547520 bytes.
Note: Testcase only tests the option variable. The actual bug has be to
tested manually.
As documented in the bug report, the double checked locking
pattern has inherent issues, and cannot guarantee correct
initialization.
This patch replaces the logic in init_available_charsets()
with the use of pthread_once(3). A wrapper function,
my_pthread_once(), is introduced and is used in lieu of direct
calls to init_available_charsets(). Related defines
MY_PTHREAD_ONCE_* are also introduced.
For the Windows platform, the implementation in lp:sysbench is
ported. For single-thread use, a simple define calls the
function and sets the pthread_once control variable.
Charset initialization is modified to use my_pthread_once().
The help text for --init-slave=name:
"Command(s) that are executed when a slave connects to this master".
This text indicate that the --init-slave option is set on a master
server, and the master server passes the option's argument to slave
which connects to it. This is wrong. Actually the --init-slave option
just can be set on a slave server, and then the slave server executes
the argument each time the SQL thread starts.
Correct the help text for --init-slave option as following:
"Command(s) that are executed by a slave server each time the SQL thread starts."
The help text for --init-slave=name:
"Command(s) that are executed when a slave connects to this master".
This text indicate that the --init-slave option is set on a master
server, and the master server passes the option's argument to slave
which connects to it. This is wrong. Actually the --init-slave option
just can be set on a slave server, and then the slave server executes
the argument each time the SQL thread starts.
Correct the help text for --init-slave option as following:
"Command(s) that are executed by a slave server each time the SQL thread starts."
This patch fixes three bugs as follows. First, aborting the server while purging
binary logs might generate orphan files due to how the purge operation was
implemented:
(purge routine - sql/log.cc - MYSQL_BIN_LOG::purge_logs)
1 - register the files to be removed in a temporary buffer.
2 - update the log-bin.index.
3 - flush the log-bin.index.
4 - erase the files whose names where register in the temporary buffer
in step 1.
Thus a failure while executing step 4 would generate an orphan file. Second,
a similar issue might happen while creating a new binary as follows:
(create routine - sql/log.cc - MYSQL_BIN_LOG::open)
1 - open the new log-bin.
2 - update the log-bin.index.
Thus a failure while executing step 1 would generate an orphan file.
To fix these issues, we record the files to be purged or created before really
removing or adding them. So if a failure happens such records can be used to
automatically remove dangling files. The new steps might be outlined as follows:
(purge routine - sql/log.cc - MYSQL_BIN_LOG::purge_logs)
1 - register the files to be removed in the log-bin.~rec~ placed in
the data directory.
2 - update the log-bin.index.
3 - flush the log-bin.index.
4 - delete the log-bin.~rec~.
(create routine - sql/log.cc - MYSQL_BIN_LOG::open)
1 - register the file to be created in the log-bin.~rec~
placed in the data directory.
2 - open the new log-bin.
3 - update the log-bin.index.
4 - delete the log-bin.~rec~.
(recovery routine - sql/log.cc - MYSQL_BIN_LOG::open_index_file)
1 - open the log-bin.index.
2 - open the log-bin.~rec~.
3 - for each file in log-bin.~rec~.
3.1 Check if the file is in the log-bin.index and if so ignore it.
3.2 Otherwise, delete it.
The third issue can be described as follows. The purge operation was allowing
to remove a file in use thus leading to the loss of data and possible
inconsistencies between the master and slave. Roughly, the routine was only
taking into account the dump threads and so if a slave was not connect the
file might be delete even though it was in use.
If --log-bin is set to a directory name with the trailing 'FN_LIBCHAR',
which will be '/' on Unix like systems, and '\\' on Windows like systems.
the basename of the binlog is empty so that the created files named
'.000001' and '.index'. It is not expected.
The same thing happened to --log-bin-index, --relay-log and
--relay-log-index options.
To resolve the problem, in these cases the program should report an error
and abort.
Bug#31621: Windows server hanging during shutdown using named pipes
and idle connection
Problem: when idle pipe connection is forcefully closed with KILL
statement or when the server goes down, thread that is closing connection
would hang infinitely in CloseHandle(). The reason for the hang is that
named pipe operations are performed synchronously. In this mode all IOs
on pipe are serialized, that is CloseHandle() will not abort ReadFile()
in another thread, but wait for ReadFile() to complete.
The fix implements asynchrnous mode for named pipes, where operation of file
are not synchronized. Read/Write operation would fire an async IO and wait for
either IO completion or timeout.
Note, that with this patch timeouts are properly handled for named pipes.
Post-review: Win32 timeout code has been fixed for named pipes and shared
memory. We do not store pointer to NET in vio structure, only the read and
write timeouts.
Implemented the server infrastructure for the fix:
1. Added a function LEX_STRING *thd_query_string(THD) to return
a LEX_STRING structure instead of char *.
This is the function that must be called in innodb instead of
thd_query()
2. Did some encapsulation in THD : aggregated thd_query and
thd_query_length into a LEX_STRING and made accessor and mutator
methods for easy code updating.
3. Updated the server code to use the new methods where applicable.
Backport from 6.0 to 5.1.
Only those sync points are included, which are used in debug_sync.test.
The Debug Sync Facility allows to place synchronization points
in the code:
open_tables(...)
DEBUG_SYNC(thd, "after_open_tables");
lock_tables(...)
When activated, a sync point can
- Send a signal and/or
- Wait for a signal
Nomenclature:
- signal: A value of a global variable that persists
until overwritten by a new signal. The global
variable can also be seen as a "signal post"
or "flag mast". Then the signal is what is
attached to the "signal post" or "flag mast".
- send a signal: Assign the value (the signal) to the global
variable ("set a flag") and broadcast a
global condition to wake those waiting for
a signal.
- wait for a signal: Loop over waiting for the global condition until
the global value matches the wait-for signal.
Please find more information in the top comment in debug_sync.cc
or in the worklog entry.
when compiled with Sun Studio compiler).
The thing is that Sun Studio compiler calls destructor of stack
objects when pthread_exit() is called. That triggered an assertion
in DBUG_ENTER()/DBUG_RETURN() validation logic (if DBUG_ENTER() is
used in the beginning of function, all returns should be replaced
by DBUG_RETURN/DBUG_VOID_RETURN macros).
A fix is to explicitly use DBUG_LEAVE macro.
When parsing the service installation parameter in
default_service_handling() make sure the value of the
optional parameter doesn't overwrite it's name.
- Define and pass compile time path variables as pre-processor definitions to
mimic the makefile build.
- Set new CMake version and policy requirements explicitly.
- Changed DATADIR to MYSQL_DATADIR to avoid conflicting definition in
Platform SDK header ObjIdl.h which also defines DATADIR.
Initialize LOCK_open as a adapative mutex on platforms where the
PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP macro is available. The flag
indicates that a thread should spin (busy wait) for some time on a
locked adaptive mutex before blocking (sleeping). It's intended to
to alleviate performance problems due to LOCK_open being a highly
contended mutex.
The maximum value of the max_join_size variable is set by converting
a signed type (long int) with negative value (-1) to a wider unsigned
type (unsigned long long), which yields the largest possible value of
the wider unsigned type -- as per the language conversion rules. But,
depending on build options, the type of the max_join_size might be a
shorter type (ha_rows - unsigned long) which causes the warning to be
thrown once the large value is truncated to fit.
The solution is to ensure that the maximum value of the variable is
always set to the maximum value of integer type of max_join_size.
Furthermore, it would be interesting to always have a fixed type for
this variable, but this would incur in a change of behavior which is
not acceptable for a GA version. See Bug#35346.
not logged
Errors encountered during initialization of the SSL subsystem
are printed to stderr, rather than to the error log.
This patch adds a parameter to several SSL init functions to
report the error (if any) out to the caller. The function
init_ssl() in mysqld.cc is moved after the initialization of
the log subsystem, so that any error messages can be logged to
the error log. Printing of messages to stderr has been
retained to get diagnostic output in a client context.
The reason for the crash was rotate_relay_log (mi=0x0) did not verify
the passed value of active_mi. There are more cases where active_mi
is supposed to be non-zero e.g change_master(), stop_slave(), and it's
reasonable to protect from a similar crash all of them with common
fixes.
Fixed with spliting end_slave() in slave threads release and slave
data clean-up parts (a new close_active_mi()). The new function is
invoked at the very end of close_connections() so that all users of
active_mi are proven to have left.
The problem: described in the bug report.
The fix:
--increase buffers where it's necessary
(buffers which are used in stxnmov)
--decrease buffer lengths which are used
variable. The problem was that THD::connect_utime could be
used without being initialized when the main thread is used
to handle connections (--thread-handling=no-threads).
always rollsback.
There is failure on pushbuild machines which are using old compilers complaining about
ULLONG_MAX declaration. Changing this to ULONGLONG_MAX to solve the problem.
always rollsback.
The global variable max_binlog_cache_size cannot be set more than 4GB on
32 bit systems, limiting transactions of all storage engines to 4G of changes.
The problem is max_binlog_cache_size is declared as ulong which is 4 bytes
on 32 bit and 8 bytes on 64 bit machines.
Fixed by using ulonglong for max_binlog_cache_size which is 8bytes on 32
and 64 bit machines.The range for max_binlog_cache_size on 32 bit and 64 bit
systems is 4096-18446744073709547520 bytes.
for indexes of InnoDB table
Fixes by replacing the PRNG that is used to pick random pages with a
better one.
Also adds a configuration option "innodb_use_legacy_cardinality_algorithm"
to enable the fix only when the option is set.
This patch is from http://bugs.mysql.com/file.php?id=11789
