This fixed the MySQL bug# 20338 about misuse of double underscore
prefix __WIN__, which was old MySQL's idea of identifying Windows
Replace it by _WIN32 standard symbol for targeting Windows OS
(both 32 and 64 bit)
Not that connect storage engine is not fixed in this patch (must be
fixed in "upstream" branch)
This change removed 68 explict strlen() calls from the code.
The following renames was done to ensure we don't use the old names
when merging code from earlier releases, as using the new variables
for print function could result in crashes:
- charset->csname renamed to charset->cs_name
- charset->name renamed to charset->coll_name
Almost everything where mechanical changes except:
- Changed to use the new Protocol::store(LEX_CSTRING..) when possible
- Changed to use field->store(LEX_CSTRING*, CHARSET_INFO*) when possible
- Changed to use String->append(LEX_CSTRING&) when possible
Other things:
- There where compiler issues with ensuring that all character set names
points to the same string: gcc doesn't allow one to use integer constants
when defining global structures (constant char * pointers works fine).
To get around this, I declared defines for each character set name
length.
Protocol_local fixed so it can be used now.
Some Protocol:: methods made virtual so they can adapt.
as well as net_ok and net_send_error functions.
execute_sql_string function is exported to the plugins.
To be changed with the mysql_use_result.
This happend when using XA transactions. I also added some extra asserts
to ensure that m_transactions are properly cleared.
Other things:
- Removed set_time() from THD::init_for_queries() as dispatch_command()
is already doing that.
- Removed duplicate init_for_queries() from prepare_new_connection_state().
The init_for_queries() functions should only be called once per
connection.
If async slave thread (slave SQL handler), becomes a BF victim, it may occasionally happen that rollbacker thread is used to carry out the rollback instead of the async slave thread.
This can happen, if async slave thread has flagged "idle" state when BF thread tries to figure out how to kill the victim.
The issue was possible to test by using a galera cluster as slave for external master, and issuing high load of conflicting writes through async replication and directly against galera cluster nodes.
However, a deterministic mtr test for the "conflict window" has not yet been worked on.
The fix, in this patch makes sure that async slave thread state is never set to IDLE. This prevents the rollbacker thread to intervene.
The wsrep_query_state change was refactored to happen by dedicated function to make controlling the idle state change in one place.
MariaDB 10.4 was crashing when thread-handling was set to
pool-of-threads and wsrep was enabled.
There were two apparent reasons for the crash:
- Connection handling in threadpool_common.cc was missing calls to
control wsrep client state.
- Thread specific storage which contains thread variables (THR_KEY_mysys)
was not handled appropriately by wsrep patch when pool-of-threads
was configured.
This patch addresses the above issues in the following way:
- Wsrep client state open/close was moved in thd_prepare_connection() and
end_connection() to have common handling for one-thread-per-connection
and pool-of-threads.
- Thread local storage handling in wsrep patch was reworked by introducing
set of wsrep_xxx_threadvars() calls which replace calls to
THD store_globals()/reset_globals() and deal with thread handling
specifics internally.
Wsrep-lib was updated to version which relaxes internal concurrency
related sanity checks.
Rollback code from wsrep_rollback_process() was extracted to separate calls
for better readability.
Post rollback thread was removed as it was completely unused.
Plugin fixed to not lock the LOCK_operations when not active.
Server fixed to lock the LOCK_plugin less - do it once per
thread and then only if a plugin was installed/uninstalled.
Removed LOCK_connection_count.
Removed duplicate denied_connections and connection_errors_max_connection
increment from create_new_thread(). Another increment done by
CONNECT::close_with_error().
Simplified away CONNECT::thread_count_incremented. Now close_with_error()
is always called with connection_count incremented.
Part of MDEV-19515 - Improve connect speed
It mostly duplicates code of do_handle_one_connection(). Move it there,
so that it is easier to simplify it in future.
Moved PSI_CALL_delete_current_thread()/_db_pop_() out of mutex. Call them
consistently in all cases, unlike before:
- called for reused threads
- called for flushed threads
- called for threads that go down after 5 minutes timeout
- not called for threads attempting to cache themselves during flush
- not called for threads attempting to cache themselves when cache is full
Part of MDEV-19515 - Improve connect speed
Code properly integrated into callers instead.
do_handle_one_connection(): no need to reset thd and thd->thread_stack
as they're not updated by cache_thread().
Part of MDEV-19515 - Improve connect speed
It was meaningful only for one-thread-per-connection scheduler anyway,
so call init_new_connection_handler_thread() directly from
handle_one_connection().
It was somewhat harmful for no-threads scheduler, because it'd attempt to
detach main thread on AIX_3_2 and Siemens unix (and DEC OSF/1 3.2 too).
Also it does duplicate my_thread_init() call, which may produce a warning
under EXTRA_DEBUG_THREADS.
start_wsrep_THD() shouldn't have called it at all: it already detached
and called my_thread_init().
Part of MDEV-19515 - Improve connect speed
It was wrong anyway, as it may not get updated by the time created thread
reads it. And it was 0 for cached threads.
Part of MDEV-19515 - Improve connect speed
The MDEV-17262 commit 26432e49d3
was skipped. In Galera 4, the implementation would seem to require
changes to the streaming replication.
In the tests archive.rnd_pos main.profiling, disable_ps_protocol
for SHOW STATUS and SHOW PROFILE commands until MDEV-18974
has been fixed.
Removed redundant plugin_thdvar_cleanup() from end_connection(): called by
THD::free_connection(), which always follows end_connection().
Saves at least one lock(LOCK_plugin) and one
rdlock(LOCK_system_variables_hash).
Benchmarked on a 2socket/20core/40threads Broadwell system using sysbench
connect brencmark @40 threads (with select 1 disabled).
10.2 shows moderate improvement: 136219.93 -> 137766.31 CPS.
10.3 is improvement is somewhat better: 93018.29 -> 101379.77 CPS.
Also backported MyRocks memory leak fix from 10.4, which turned out to
be unrelated.
