The pthread_cond_timedwait(3P) api
uses a const struct timespec for parameter 3.
The instrumentation api for the same, mysql_cond_timedwait,
which expands to inline_mysql_cond_timedwait,
should also take a const parameter for the timespec.
This fix add the missing const to inline_mysql_cond_timedwait.
- Added --verbose to BUILD scripts to get make to write out compile commands.
- Detect if AM_EXTRA_MAKEFLAGS=VERBOSE=1 was used with build scripts.
- Don't write warnings about replication variables when doing bootstrap.
- Fixed that mysql_cond_wait() and mysql_cond_timedwait() will report original source file in case of errors.
- Ignore some compiler warnings
BUILD/FINISH.sh:
Detect if AM_EXTRA_MAKEFLAGS=VERBOSE=1 or --verbose was used
BUILD/SETUP.sh:
Added --verbose to print out the full compile lines
Updated help message
client/mysqltest.cc:
Fixed that one can use 'replace' with cat_file
cmake/configure.pl:
If --verbose is used, get make to write out compile commands
debian/dist/Debian/rules:
Added $AM_EXTRA_MAKEFLAGS to get VERBOSE=1 on buildbot builds
debian/dist/Ubuntu/rules:
Added $AM_EXTRA_MAKEFLAGS to get VERBOSE=1 on buildbot builds
include/my_pthread.h:
Made set_timespec_time_nsec() more portable.
include/mysql/psi/mysql_thread.h:
Fixed that mysql_cond_wait() and mysql_cond_timedwait() will report original source file in case of errors.
mysql-test/suite/innodb/r/auto_increment_dup.result:
Fixed wrong DBUG_SYNC
mysql-test/suite/innodb/t/auto_increment_dup.test:
Fixed wrong DBUG_SYNC
mysql-test/suite/perfschema/include/upgrade_check.inc:
Make test more portable for changes in *.sql files
mysql-test/suite/perfschema/r/pfs_upgrade.result:
Updated test results
mysql-test/valgrind.supp:
Ignore running Aria checkpoint thread
scripts/mysqlaccess.sh:
Changed reference of bugs database
Ensure that also client-server group is read.
sql/handler.cc:
Added missing syncpoint
sql/mysqld.cc:
Don't write warnings about replication variables when doing bootstrap
sql/mysqld.h:
Don't write warnings about replication variables when doing bootstrap
sql/rpl_rli.cc:
Don't write warnings about replication variables when doing bootstrap
sql/sql_insert.cc:
Don't mask SERVER_SHUTDOWN in insert_delayed
This is done to be able to distingush between shutdown and interrupt errors
support-files/compiler_warnings.supp:
Ignore some compiler warnings in xtradb,innobase, oqgraph, yassl, string3.h
detector" that doesn't introduce bug #56715 "Concurrent
transactions + FLUSH result in sporadical unwarranted
deadlock errors".
Deadlock could have occurred when workload containing a mix
of DML, DDL and FLUSH TABLES statements affecting the same
set of tables was executed in a heavily concurrent environment.
This deadlock occurred when several connections tried to
perform deadlock detection in the metadata locking subsystem.
The first connection started traversing wait-for graph,
encountered a sub-graph representing a wait for flush, acquired
LOCK_open and dived into sub-graph inspection. Then it
encountered sub-graph corresponding to wait for metadata lock
and blocked while trying to acquire a rd-lock on
MDL_lock::m_rwlock, since some,other thread had a wr-lock on it.
When this wr-lock was released it could have happened (if there
was another pending wr-lock against this rwlock) that the rd-lock
from the first connection was left unsatisfied but at the same
time the new rd-lock request from the second connection sneaked
in and was satisfied (for this to be possible the second
rd-request should come exactly after the wr-lock is released but
before pending the wr-lock manages to grab rwlock, which is
possible both on Linux and in our own rwlock implementation).
If this second connection continued traversing the wait-for graph
and encountered a sub-graph representing a wait for flush it tried
to acquire LOCK_open and thus the deadlock was created.
The previous patch tried to workaround this problem by not
allowing the deadlock detector to lock LOCK_open mutex if
some other thread doing deadlock detection already owns it
and current search depth is greater than 0. Instead deadlock
was reported. As a result it has introduced bug #56715.
This patch solves this problem in a different way.
It introduces a new rw_pr_lock_t implementation to be used
by MDL subsystem instead of one based on Linux rwlocks or
our own rwlock implementation. This new implementation
never allows situation in which an rwlock is rd-locked and
there is a blocked pending rd-lock. Thus the situation which
has caused this bug becomes impossible with this implementation.
Due to fact that this implementation is optimized for
wr-lock/unlock scenario which is most common in the MDL
subsystem it doesn't introduce noticeable performance
regressions in sysbench tests. Moreover it significantly
improves situation for POINT_SELECT test when many
connections are used.
No test case is provided as this bug is very hard to repeat
in MTR environment but is repeatable with the help of RQG
tests.
This patch also doesn't include a test for bug #56715
"Concurrent transactions + FLUSH result in sporadical
unwarranted deadlock errors" as it takes too much time to
be run as part of normal test-suite runs.
config.h.cmake:
We no longer need to check for presence of
pthread_rwlockattr_setkind_np as we no longer
use Linux-specific implementation of rw_pr_lock_t
which uses this function.
configure.cmake:
We no longer need to check for presence of
pthread_rwlockattr_setkind_np as we no longer
use Linux-specific implementation of rw_pr_lock_t
which uses this function.
configure.in:
We no longer need to check for presence of
pthread_rwlockattr_setkind_np as we no longer
use Linux-specific implementation of rw_pr_lock_t
which uses this function.
include/my_pthread.h:
Introduced new implementation of rw_pr_lock_t.
Since it never allows situation in which rwlock is rd-locked
and there is a blocked pending rd-lock it is not affected by
bug #56405 "Deadlock in the MDL deadlock detector".
This implementation is also optimized for wr-lock/unlock
scenario which is most common in MDL subsystem. So it doesn't
introduce noticiable performance regressions in sysbench tests
(compared to old Linux-specific implementation). Moreover it
significantly improves situation for POINT_SELECT test when
many connections are used.
As part of this change removed try-lock part of API for
this type of lock. It is not used in our code and it would
be hard to implement correctly within constraints of new
implementation.
Finally, removed support of preferring readers from
my_rw_lock_t implementation as the only user of this
feature was old rw_pr_lock_t implementation.
include/mysql/psi/mysql_thread.h:
Removed try-lock part of prlock API.
It is not used in our code and it would be hard
to implement correctly within constraints of new
prlock implementation.
mysys/thr_rwlock.c:
Introduced new implementation of rw_pr_lock_t.
Since it never allows situation in which rwlock is rd-locked
and there is a blocked pending rd-lock it is not affected by
bug #56405 "Deadlock in the MDL deadlock detector".
This implementation is also optimized for wr-lock/unlock
scenario which is most common in MDL subsystem. So it doesn't
introduce noticiable performance regressions in sysbench tests
(compared to old Linux-specific implementation). Moreover it
significantly improves situation for POINT_SELECT test when
many connections are used.
Also removed support of preferring readers from
my_rw_lock_t implementation as the only user of this
feature was old rw_pr_lock_t implementation.
Implement a few simple asserts in my_rwlock_t locks.
include/my_pthread.h:
Declare two simple assert functions.
include/mysql/psi/mysql_thread.h:
Add wrappers for new assert functions.
mysys/thr_rwlock.c:
Add asserts.
sql/sql_base.cc:
Silence a compiler warning for the case when
SAFE_MUTEX is not ON.
This change is for performance optimization.
Fixed the performance schema instrumentation interface as follows:
- simplified mysql_unlock_mutex()
- simplified mysql_unlock_rwlock()
- simplified mysql_cond_signal()
- simplified mysql_cond_broadcast()
Changed the get_thread_XXX_locker apis to have one extra parameter,
to provide memory to the instrumentation implementation.
This API change allows to use memory provided by the caller,
to avoid having to use thread local storage.
Using this extra parameter will be done in a separate fix,
this change is for the interface only.
Adjusted all the code and unit tests accordingly.
This is a fix specific for HPUX,
for which the compiler does not resolve properly dependencies
involving unused inline functions.
(See existing comments in mysql_thread.h)
In include/mysql/psi/mysql_thread.h,
the instrumentation helpers for mysql_prlock_*
uses the pr lock apis.
These apis are implemented in mysys/thr_rwlock.c,
which is not linked to client code.
As a result, the code does not link in libmysql_r, on HPUX.
The fix is to cut dependencies explicitely,
by introducing -DDISABLE_MYSQL_RWLOCK_H,
when building client code.
Before this fix, the performance schema instrumentation
in mdl.h / mdl.cc was incomplete, causing:
- build warnings,
- no data collection for the performance schema
This fix:
- added instrumentation helpers for the new preferred
reader read write lock, mysql_prlock_*
- implemented completely the performance schema
instrumentation of mdl.h / mdl.cc
