mirror of
https://github.com/MariaDB/server.git
synced 2025-07-27 21:55:03 +02:00
bead24b7f3
Remove one of the major sources of race condiitons in mariadb-test. Normally, mariadb_close() sends COM_QUIT to the server and immediately disconnects. In mariadb-test it means the test can switch to another connection and sends queries to the server before the server even started parsing the COM_QUIT packet and these queries can see the connection as fully active, as it didn't reach dispatch_command yet. This is a major source of instability in tests and many - but not all, still less than a half - tests employ workarounds. The correct one is a pair count_sessions.inc/wait_until_count_sessions.inc. Also very popular was wait_until_disconnected.inc, which was completely useless, because it verifies that the connection is closed, and after disconnect it always is, it didn't verify whether the server processed COM_QUIT. Sadly the placebo was as widely used as the real thing. Let's fix this by making mariadb-test `disconnect` command _to wait_ for the server to confirm. This makes almost all workarounds redundant. In some cases count_sessions.inc/wait_until_count_sessions.inc is still needed, though, as only `disconnect` command is changed: * after external tools, like `exec $MYSQL` * after failed `connect` command * replication, after `STOP SLAVE` * Federated/CONNECT/SPIDER/etc after `DROP TABLE` and also in some XA tests, because an XA transaction is dissociated from the THD very late, after the server has closed the client connection. Collateral cleanups: fix comments, remove some redundant statements: * DROP IF EXISTS if nothing is known to exist * DROP table/view before DROP DATABASE * REVOKE privileges before DROP USER etc
46 lines
1.5 KiB
Text
46 lines
1.5 KiB
Text
connect con1, localhost, root, , ;
|
|
connect con2, localhost, root, , ;
|
|
connect con3, localhost, root, , ;
|
|
connection default;
|
|
update performance_schema.setup_instruments set enabled='YES'
|
|
where name like "wait/synch/mutex/mysys/THR_LOCK_myisam";
|
|
drop table if exists test.t1;
|
|
drop table if exists test.t2;
|
|
drop table if exists test.t3;
|
|
truncate table performance_schema.events_waits_history_long;
|
|
show global variables like "thread_handling";
|
|
Variable_name Value
|
|
thread_handling one-thread-per-connection
|
|
connection con1;
|
|
create table test.t1(a int) engine=MYISAM;
|
|
connection con2;
|
|
create table test.t2(a int) engine=MYISAM;
|
|
connection con3;
|
|
create table test.t3(a int) engine=MYISAM;
|
|
connection default;
|
|
execute stmt_dump_events using @tid;
|
|
event_name short_source operation number_of_bytes
|
|
wait/synch/mutex/mysys/THR_LOCK_myisam lock NULL
|
|
execute stmt_dump_thread using @tid;
|
|
name
|
|
thread/sql/one_connection
|
|
execute stmt_dump_events using @tid;
|
|
event_name short_source operation number_of_bytes
|
|
wait/synch/mutex/mysys/THR_LOCK_myisam lock NULL
|
|
execute stmt_dump_thread using @tid;
|
|
name
|
|
thread/sql/one_connection
|
|
execute stmt_dump_events using @tid;
|
|
event_name short_source operation number_of_bytes
|
|
wait/synch/mutex/mysys/THR_LOCK_myisam lock NULL
|
|
execute stmt_dump_thread using @tid;
|
|
name
|
|
thread/sql/one_connection
|
|
drop table test.t1;
|
|
drop table test.t2;
|
|
drop table test.t3;
|
|
update performance_schema.setup_instruments set enabled='YES';
|
|
disconnect con1;
|
|
disconnect con2;
|
|
disconnect con3;
|
|
connection default;
|