This commit is for optimizing WSREP(thd) macro.
#define WSREP(thd) \
(WSREP_ON && wsrep && (thd && thd->variables.wsrep_on))
In this we can safely remove wsrep and thd. We are not removing WSREP_ON
because this will change WSREP(thd) behaviour.
Patch Credit:- Nirbhay Choubay, Sergey Vojtovich
Tasks:-
Changes in wsrep_dirty_reads variable
1.) Global + Session scope (Current: session-only)
2.) Can be set using command line.
3.) Allow all commands that do not change data (besides SELECT)
4.) Allow prepared Statements that do not change data
5.) Works with wsrep_sync_wait enabled
- At startup time global wsrep_on is set too late and some wsrep paths may be executed
because of this. e.g. replication slave restart could happen before wsrep_on state is defined.
- This fix checks both global wsrep_on and wsrep_provider values to determine if wsrep
processing should happen
- Fix affects all instances where WSREP_ON macro is used
- changed the condition when to do implicit desync as part of FTWRL to
cover only case when node is PC and synced. Donor node has alreaydy desycned
and other states mean that node is not in cluster, so desync is not even possible.
- reverted from tracking donor servicing thread. With xtrabackup SST,
xtrabackup thread will call FTWRL and node is desynced upfront
- Skipping desync in FTWRL if node is operating as donor
- Fixes query cache so that it is aware of wsrep_sync_wait.
Query cache would return (possibly stale) results to the
client, regardless of the value of wsrep_sync_wait.
- Includes the test case that reproduced the issue.
different fix. remove old ones, wait for THD to be fully
initialized before continuing with the server startup process.
This reverts commits db2e21b, 13615c5, 3f515a0, 70113ee.
As galera node (slave) received query log events from an async
replication master, it partially wrote the updates made to replication
state table (mysql.gtid_slave_pos) to galera transaction writeset post
TOI. As a result, the transaction handle, thus created within galera,
was never freed/purged as the corresponding trx did not commit.
Thus, it kept piling up for every query log event and was only reclaimed
upon server shutdown when the transaction map object got destructed.
Fixed by making sure that updates in replication slave state table
are not written to galera transaction writeset and thus, not replicated
to other nodes.
Problem:
When mysqld starts as a galera node, it creates 2 system threads
(applier & rollbacker) using start_wsrep_THD(). These threads are
created before plugin initialization (plugin_init()) for SST methods
like rsync and xtrabackup.
The threads' initialization itself can proceed in parallel to mysqld's
main thread of execution. As a result, the thread initialization code
(start_wsrep_THD()) can end up accessing some un/partially initialized
structures (like maria_hton, in this particular case) resulting in
segfault.
Solution:
Fixed by calling THD::init_for_queries() (which accesses maria_hton)
only after the plugins have been initialized.
Problem:
When mysqld starts as a galera node, it creates 2 system threads
(applier & rollbacker) using start_wsrep_THD(). These threads are
created before plugin initialization (plugin_init()) for SST methods
like rsync and xtrabackup.
The threads' initialization itself can proceed in parallel to mysqld's
main thread of execution. As a result, the thread initialization code
(start_wsrep_THD()) can end up accessing some un/partially initialized
structures (like maria_hton, in this particular case) resulting in
segfault.
Solution:
Fixed by calling THD::init_for_queries() (which accesses maria_hton)
only after the plugins have been initialized.
* mysqld_safe: Since wsrep_on variable is mandatory in 10.1, skip wsrep
position recovery if its OFF.
* mysqld: Remove "-wsrep" from server version
* mysqld: Remove wsrep patch version from @@version_comment
* mysqld: Introduce @@wsrep_patch_version
Sidno initialization was skipped in wsrep_sst_received() if the
received position matched to current position. However, sidno
initialization must be done every time server is started to
add inverted group uuid into sidno map.
1. factored XID-related functions to a separate wsrep_xid.cc unit.
2. refactored them to take refrences instead of pointers where appropriate
3. implemented wsrep_get/set_SE_position to take wsrep_uuid_t and wsrep_seqno_t instead of XID
4. call wsrep_set_SE_position() in wsrep_sst_received() to reinitialize SE checkpoint after SST was received, avoid assert() in setting code by first checking current position.
Added MAX_STATEMENT_TIME user variable to automaticly kill queries after a given time limit has expired.
- Added timer functions based on pthread_cond_timedwait
- Added kill_handlerton() to signal storage engines about kill/timeout
- Added support for GRANT ... MAX_STATEMENT_TIME=#
- Copy max_statement_time to current user, if stored in mysql.user
- Added status variable max_statement_time_exceeded
- Added KILL_TIMEOUT
- Removed digest hash from performance schema tests as they change all the time.
- Updated test results that changed because of the new user variables or new fields in mysql.user
This functionallity is inspired by work done by Davi Arnaut at twitter.
Test case is copied from Davi's work.
Documentation can be found at
https://kb.askmonty.org/en/how-to-limittimeout-queries/
mysql-test/r/mysqld--help.result:
Updated for new help message
mysql-test/suite/perfschema/r/all_instances.result:
Added new mutex
mysql-test/suite/sys_vars/r/max_statement_time_basic.result:
Added testing of max_statement_time
mysql-test/suite/sys_vars/t/max_statement_time_basic.test:
Added testing of max_statement_time
mysql-test/t/max_statement_time.test:
Added testing of max_statement_time
mysys/CMakeLists.txt:
Added thr_timer
mysys/my_init.c:
mysys/mysys_priv.h:
Added new mutex and condition variables
Added new mutex and condition variables
mysys/thr_timer.c:
Added timer functions based on pthread_cond_timedwait()
This can be compiled with HAVE_TIMER_CREATE to benchmark agains timer_create()/timer_settime()
sql/lex.h:
Added MAX_STATEMENT_TIME
sql/log_event.cc:
Safety fix (timeout should be threated as an interrupted query)
sql/mysqld.cc:
Added support for timers
Added status variable max_statement_time_exceeded
sql/share/errmsg-utf8.txt:
Added ER_QUERY_TIMEOUT
sql/signal_handler.cc:
Added support for KILL_TIMEOUT
sql/sql_acl.cc:
Added support for GRANT ... MAX_STATEMENT_TIME=#
Copy max_statement_time to current user
sql/sql_class.cc:
Added timer functionality to THD.
Added thd_kill_timeout()
sql/sql_class.h:
Added timer functionality to THD.
Added KILL_TIMEOUT
Added max_statement_time variable in similar manner as long_query_time was done.
sql/sql_connect.cc:
Added handling of max_statement_time_exceeded
sql/sql_parse.cc:
Added starting and stopping timers for queries.
sql/sql_show.cc:
Added max_statement_time_exceeded for user/connects status in MariaDB 10.0
sql/sql_yacc.yy:
Added support for GRANT ... MAX_STATEMENT_TIME=# syntax, to be enabled in 10.0
sql/structs.h:
Added max_statement_time user resource
sql/sys_vars.cc:
Added max_statement_time variables
mysql-test/suite/roles/create_and_drop_role_invalid_user_table.test
Removed test as we require all fields in mysql.user table.
scripts/mysql_system_tables.sql
scripts/mysql_system_tables_data.sql
scripts/mysql_system_tables_fix.sql
Updated mysql.user with new max_statement_time field
Merged lp:maria/maria-10.0-galera up to revision 3879.
Added a new functions to handler API to forcefully abort_transaction,
producing fake_trx_id, get_checkpoint and set_checkpoint for XA. These
were added for future possiblity to add more storage engines that
could use galera replication.
