Commit f4781a7e authored by unknown's avatar unknown
Browse files

fix for bug #17619 Scheduler race conditions 

- Scheduler is either initialized at server start or never.
  Starting & stopping is now suspending & resuming.
- The scheduler has clear OO interface
- Now all calls to the scheduler are synchronous
- GLOBAL event_scheduler uses thd::sys_var_tmp (see set_var.cc)
- External API is encapsulated into class Events
- Includes fixes for all comments of Kostja's review of 19.05.2005

Starting to merge into 5.1-release (5.1.10) and push


BitKeeper/etc/ignore:
  Added libmysqld/event_scheduler.cc to the ignore list
libmysqld/Makefile.am:
  executor -> scheduler
mysql-test/r/events.result:
  update result
mysql-test/r/events_bugs.result:
  update result
mysql-test/r/events_logs_tests.result:
  update result
mysql-test/r/events_microsec.result:
  update result
mysql-test/r/events_scheduling.result:
  update result
mysql-test/r/events_stress.result:
  update result
mysql-test/t/disabled.def:
  enable these tests
mysql-test/t/events.test:
  optimize the test a bit for speed, save some seconds runtime
  remove FULL from SHOW EVENTS
  mostly use I_S.EVENTS
mysql-test/t/events_bugs.test:
  Skip irrelevant for the current design tests - all events are loaded
  on server startup. Change in mysql.event will be visible on next server start.
  Don't use numeric error codes.
mysql-test/t/events_logs_tests.test:
  optimize the test a bit for speed
mysql-test/t/events_microsec.test:
   Skip irrelevant for the current design tests - all events are loaded
      on server startup. Change in mysql.event will be visible on next server start.
      Don't use numeric error codes.
mysql-test/t/events_scheduling.test:
  broader test
mysql-test/t/events_stress.test:
  Rework the test to the new architecture of suspending/resuming.
  Use less events, no need for thousands, hundreds is still ok.
sql/Makefile.am:
  executor -> scheduler
sql/cmakelists.txt:
  executor -> scheduler
sql/event.cc:
  - remove todo comments
  - remove unneded evex_queue abstraction functions
  - move events_init() and events_shutdown() from event_executor.cc to here
  - export db_create_event
  - remove evex_load_and_compile_event, part of class Event_scheduler
  - integrate the public interface found in event.h and used by sql_parse.cc
    to use the new class Event_scheduler.
sql/event.h:
  - add COND_finished so if one thread kills a running event it waits on this
  - export callback event_timed_definer_equal, event_timed_identifier_equal(),
    event_timed_name_equal and event_timed_db_equal()
    to be used by Event_scheduler::drop_matching_events()
  - cleanup event.h
  - encapsulated all external interface into class Events
sql/event_executor.cc:
  make it empty, will delete after that
sql/event_priv.h:
  - more things in the private header
  - remove event queue abstraction functions. tightly bind to QUEUE
  - export privately db_drop_event, db_find_event, db_create_event()
  - made change_security_context() and restore_security_context() free functions
sql/event_timed.cc:
  - fix calculation of time when ENDS is set (STARTS is always set)
  - during Event_timed::compile() set the right Security_ctx. Prevents a crash
        during Event_scheduler::load_events_from_db()
  - add Event_timed::kill_thread()
  - implement event_timed_*_equal()
  - made change_security_context() and restore_security_context() free functions.
  - Comments cleanups
sql/lex.h:
  new word scheduler for SHOW SCHEDULER STATUS (available only debug builds)
sql/log.cc:
  move these from event_scheduler.cc
sql/mysql_priv.h:
  refactor kill_one_thread
  export sql_print_message_func and sql_print_message_handlers
sql/mysqld.cc:
  In close_connections, called by kill_server() skip the main scheduler
  thread and use events_shutdown() for shutting down the scheduler, in the same
  manner it's done for RPL.
  Add a new value to --event-scheduler :
  0 <- No scheduler available
  1 <- Start with scheduler enabled
  2 <- Start with scheduler suspended
sql/repl_failsafe.cc:
  refactor thd::system_thread to be an enum
sql/set_var.cc:
  move sys_var_event_executor::update() to set_var.cc
  executor -> scheduler
  use thd::sys_var_tmp
sql/set_var.h:
  executor -> scheduler
sql/share/errmsg.txt:
  3 new error messages
sql/sql_class.cc:
  refactor thd::system_thread to be an enum . more type-safety
sql/sql_class.h:
  refactor thd::system_thread to be an enum . more type-safety
sql/sql_db.cc:
  get the error from evex_drop_schema_events
sql/sql_error.h:
  export warning_level_names
sql/sql_lex.h:
  new command SHOW SCHEDULER STATUS, available only in debug build and
  for debug purposes.
sql/sql_parse.cc:
  refactor kill_one_thread() -> does the *dirty* work, and sql_kill
  just the reporting.
  add handler for SQLCOM_SHOW_SCHEDULER_STATUS
sql/sql_show.cc:
  fix verbosity handling (this will be obsoleted anyway by the fix for 17394).
sql/sql_yacc.yy:
  remove FULL from SHOW EVENTS
  add SHOW SCHEDULER STATUS in debug builds
sql/table.cc:
  Fix valgrind warning.
parent 61bd3fa0

.bzrignore

+1 −0
Original line number Diff line number Diff line
@@ -1770,3 +1770,4 @@ vio/viotest-sslconnect.cpp 
vio/viotest.cpp

zlib/*.ds?

zlib/*.vcproj

libmysqld/event_scheduler.cc

libmysqld/Makefile.am

+1 −1
Original line number Diff line number Diff line
@@ -68,7 +68,7 @@ sqlsources = derror.cc field.cc field_conv.cc strfunc.cc filesort.cc \ 
	spatial.cc gstream.cc sql_help.cc tztime.cc sql_cursor.cc \

	sp_head.cc sp_pcontext.cc sp.cc sp_cache.cc sp_rcontext.cc \

	parse_file.cc sql_view.cc sql_trigger.cc my_decimal.cc \

	event_executor.cc event.cc event_timed.cc \

	event_scheduler.cc event.cc event_timed.cc \

	rpl_filter.cc sql_partition.cc sql_builtin.cc sql_plugin.cc \

	sql_tablespace.cc \

	rpl_injector.cc my_user.c partition_info.cc

mysql-test/r/events.result

+25 −27
Original line number Diff line number Diff line
@@ -17,13 +17,13 @@ db_x 
SHOW TABLES FROM db_x;

Tables_in_db_x

x_table

SET GLOBAL event_scheduler=0;

SET GLOBAL event_scheduler=2;

DROP EVENT e_x1;

DROP EVENT e_x2;

DROP DATABASE db_x;

DROP USER pauline@localhost;

USE events_test;

SET GLOBAL event_scheduler=0;

SET GLOBAL event_scheduler=2;

drop event if exists event1;

Warnings:

Note	1305	Event event1 does not exist
@@ -100,7 +100,7 @@ a 
800219

drop event non_qualif_ev;

drop table non_qualif;

set global event_scheduler = 0;

set global event_scheduler = 2;

create table t_event3 (a int, b float);

drop event if exists event3;

Warnings:
@@ -324,18 +324,18 @@ events_test one_event ev_test@localhost RECURRING NULL 20 SECOND # # ENABLED 
events_test	three_event	ev_test@localhost	RECURRING	NULL	20	SECOND	#	#	ENABLED

events_test	two_event	ev_test@localhost	RECURRING	NULL	20	SECOND	#	#	ENABLED

"This should show us only 3 events:";

SHOW FULL EVENTS;

SHOW EVENTS;

Db	Name	Definer	Type	Execute at	Interval value	Interval field	Starts	Ends	Status

events_test	one_event	ev_test@localhost	RECURRING	NULL	20	SECOND	#	#	ENABLED

events_test	three_event	ev_test@localhost	RECURRING	NULL	20	SECOND	#	#	ENABLED

events_test	two_event	ev_test@localhost	RECURRING	NULL	20	SECOND	#	#	ENABLED

"This should show us only 2 events:";

SHOW FULL EVENTS LIKE 't%event';

SHOW EVENTS LIKE 't%event';

Db	Name	Definer	Type	Execute at	Interval value	Interval field	Starts	Ends	Status

events_test	three_event	ev_test@localhost	RECURRING	NULL	20	SECOND	#	#	ENABLED

events_test	two_event	ev_test@localhost	RECURRING	NULL	20	SECOND	#	#	ENABLED

"This should show us no events:";

SHOW FULL EVENTS FROM test LIKE '%';

SHOW EVENTS FROM test LIKE '%';

Db	Name	Definer	Type	Execute at	Interval value	Interval field	Starts	Ends	Status

DROP DATABASE events_test2;

"should see 1 event:";
@@ -343,11 +343,8 @@ SHOW EVENTS; 
Db	Name	Definer	Type	Execute at	Interval value	Interval field	Starts	Ends	Status

events_test	one_event	root@localhost	RECURRING	NULL	10	SECOND	#	#	ENABLED

"we should see 4 events now:";

SHOW FULL EVENTS;

SHOW EVENTS;

Db	Name	Definer	Type	Execute at	Interval value	Interval field	Starts	Ends	Status

events_test	one_event	ev_test@localhost	RECURRING	NULL	20	SECOND	#	#	ENABLED

events_test	three_event	ev_test@localhost	RECURRING	NULL	20	SECOND	#	#	ENABLED

events_test	two_event	ev_test@localhost	RECURRING	NULL	20	SECOND	#	#	ENABLED

events_test	one_event	root@localhost	RECURRING	NULL	10	SECOND	#	#	ENABLED

SELECT EVENT_CATALOG, EVENT_SCHEMA, EVENT_NAME, DEFINER, EVENT_BODY, EVENT_TYPE, EXECUTE_AT, INTERVAL_VALUE, INTERVAL_FIELD, STATUS,ON_COMPLETION, EVENT_COMMENT from information_schema.events;

EVENT_CATALOG	EVENT_SCHEMA	EVENT_NAME	DEFINER	EVENT_BODY	EVENT_TYPE	EXECUTE_AT	INTERVAL_VALUE	INTERVAL_FIELD	STATUS	ON_COMPLETION	EVENT_COMMENT
@@ -373,12 +370,12 @@ ERROR HY000: Incorrect AT value: 'definitely not a datetime' 
set names utf8;

create event задачка on schedule every 123 minute starts now() ends now() + interval 1 month do select 1;

drop event задачка;

set event_scheduler=0;

set event_scheduler=2;

ERROR HY000: Variable 'event_scheduler' is a GLOBAL variable and should be set with SET GLOBAL

set global event_scheduler=2;

ERROR 42000: Variable 'event_scheduler' can't be set to the value of '2'

set global event_scheduler=3;

ERROR 42000: Variable 'event_scheduler' can't be set to the value of '3'

"DISABLE the scheduler. Testing that it does not work when the variable is 0"

set global event_scheduler=0;

set global event_scheduler=2;

select definer, name, db from mysql.event;

definer	name	db

select get_lock("test_lock1", 20);
@@ -389,9 +386,10 @@ create event закачка on schedule every 10 hour do select get_lock("test_l 
select definer, name, db from mysql.event;

definer	name	db

root@localhost	закачка	events_test

"Should be 0 processes"

"Should be only 1 process"

select /*1*/ user, host, db, command, state, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;

user	host	db	command	state	info

event_scheduler	localhost	NULL	Connect	Suspended	NULL

select release_lock("test_lock1");

release_lock("test_lock1")

1
@@ -409,11 +407,12 @@ get_lock("test_lock2", 20) 
create event закачка on schedule every 10 hour do select get_lock("test_lock2", 20);

"Let some time pass to the event starts"

"Should have only 2 processes: the scheduler and the locked event"

select /*1*/ user, host, db, command, state, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;

select /*2*/ user, host, db, command, state, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;

user	host	db	command	state	info

event_scheduler	localhost	NULL	Connect	Sleeping	NULL

root	localhost	events_test	Connect	User lock	select get_lock("test_lock2", 20)

"Release the mutex, the event worker should finish."

"Release the mutex, the event worker should finish."

select release_lock("test_lock2");

release_lock("test_lock2")

1
@@ -423,21 +422,17 @@ select get_lock("test_lock2_1", 20); 
get_lock("test_lock2_1", 20)

1

create event закачка21 on schedule every 10 hour do select get_lock("test_lock2_1", 20);

"Should see 1 process, locked on get_lock("

"Shutting down the scheduler, it should wait for the running event"

set global event_scheduler=0;

"Should have only 2 processes: the scheduler and the locked event"

select /*4*/ user, host, db, command, state, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;

"Should have only 3 processes: the scheduler, our conn and the locked event"

select /*3*/ user, host, db, command, state, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;

user	host	db	command	state	info

event_scheduler	localhost	NULL	Connect	Sleeping	NULL

root	localhost	events_test	Connect	User lock	select get_lock("test_lock2_1", 20)

"Release the lock so the child process should finish. Hence the scheduler also"

select release_lock("test_lock2_1");

release_lock("test_lock2_1")

1

"Should see 0 processes now:"

select /*5*/ user, host, db, command, state, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;

set global event_scheduler=2;

"Should have only our process now:"

select /*4*/ user, host, db, command, state, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;

user	host	db	command	state	info

event_scheduler	localhost	NULL	Connect	Suspended	NULL

root	localhost	events_test	Connect	User lock	select get_lock("test_lock2_1", 20)

drop event закачка21;

create table t_16 (s1 int);

create trigger t_16_bi before insert on t_16 for each row create event  e_16 on schedule every 1 second do set @a=5;
@@ -457,6 +452,9 @@ select 2; 
select event_schema, event_name, definer, event_body from information_schema.events where event_name='white_space';

event_schema	event_name	definer	event_body

events_test	white_space	root@localhost	select 2

select event_schema, event_name, definer, event_body from information_schema.events where event_name='white_space';

event_schema	event_name	definer	event_body

events_test	white_space	root@localhost	select 2

drop event white_space;

create event white_space on schedule every 10 hour disable do	select 3;

select event_schema, event_name, definer, event_body from information_schema.events where event_name='white_space';

mysql-test/r/events_bugs.result

+4 −4
Original line number Diff line number Diff line
@@ -35,7 +35,7 @@ create event e_55 on schedule every 10 hour starts 99990101000000 do drop table 
ERROR HY000: Incorrect STARTS value: '99990101000000'

create event e_55 on schedule every 10 minute ends 99990101000000 do drop table t;

ERROR HY000: ENDS is either invalid or before STARTS

set global event_scheduler=0;

set global event_scheduler=2;

"Wait a bit to settle down"

delete from mysql.event;

set global event_scheduler= 1;
@@ -57,7 +57,7 @@ root localhost events_test Connect User lock select get_lock('test_bug16407', 60 
select release_lock('test_bug16407');

release_lock('test_bug16407')

1

set global event_scheduler= 0;

set global event_scheduler= 2;

select event_schema, event_name, sql_mode from information_schema.events order by event_schema, event_name;

event_schema	event_name	sql_mode

events_test	e_16407	REAL_AS_FLOAT,PIPES_AS_CONCAT,ANSI_QUOTES,IGNORE_SPACE,ANSI
@@ -115,7 +115,7 @@ release_lock('ee_16407_2') 
select /*3*/ user, host, db, command, state, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;

user	host	db	command	state	info

event_scheduler	localhost	NULL	Connect	Sleeping	NULL

set global event_scheduler= 0;

set global event_scheduler= 2;

select * from events_smode_test order by ev_name, a;

ev_name	a

ee_16407_3	1980-02-19
@@ -175,7 +175,7 @@ drop event ee_16407_5; 
drop event ee_16407_6;

drop procedure ee_16407_5_pendant;

drop procedure ee_16407_6_pendant;

set global event_scheduler= 0;

set global event_scheduler= 2;

drop table events_smode_test;

set sql_mode=@old_sql_mode;

drop database events_test;

mysql-test/r/events_logs_tests.result

+12 −11
Original line number Diff line number Diff line
@@ -8,7 +8,7 @@ BEGIN 
SELECT user_host, argument FROM mysql.general_log WHERE argument LIKE '%alabala%';

END|

"Check General Query Log"

SET GLOBAL event_scheduler=0;

SET GLOBAL event_scheduler=2;

create event log_general on schedule every 1 minute do SELect 'alabala', sleep(3) from dual;

TRUNCATE mysql.general_log;

"1 row, the current statement!"
@@ -22,7 +22,7 @@ user_host argument 
root[root] @ localhost [localhost]	SELect 'alabala', sleep(3) from dual

DROP PROCEDURE select_general_log;

DROP EVENT log_general;

SET GLOBAL event_scheduler=0;

SET GLOBAL event_scheduler=2;

"Check slow query log"

"Save the values"

SET @old_global_long_query_time:=(select get_value());
@@ -36,14 +36,14 @@ SELECT user_host, query_time, db, sql_text FROM mysql.slow_log; 
user_host	query_time	db	sql_text

"Set new values"

SET GLOBAL long_query_time=4;

SET SESSION long_query_time=2;

SET SESSION long_query_time=1;

"Check that logging is working"

SELECT SLEEP(3);

SLEEP(3)

SELECT SLEEP(2);

SLEEP(2)

0

SELECT user_host, query_time, db, sql_text FROM mysql.slow_log;

user_host	query_time	db	sql_text

root[root] @ localhost []	SLEEPVAL	events_test	SELECT SLEEP(3)

root[root] @ localhost []	SLEEPVAL	events_test	SELECT SLEEP(2)

TRUNCATE mysql.slow_log;

CREATE TABLE slow_event_test (slo_val tinyint, val tinyint);

"This won't go to the slow log"
@@ -54,7 +54,7 @@ SET GLOBAL event_scheduler=1; 
"Sleep some more time than the actual event run will take"

SHOW VARIABLES LIKE 'event_scheduler';

Variable_name	Value

event_scheduler	ON

event_scheduler	1

"Check our table. Should see 1 row"

SELECT * FROM slow_event_test;

slo_val	val
@@ -64,18 +64,19 @@ SELECT user_host, query_time, db, sql_text FROM mysql.slow_log; 
user_host	query_time	db	sql_text

"This should go to the slow log"

SET SESSION long_query_time=10;

SET GLOBAL long_query_time=1;

DROP EVENT long_event;

CREATE EVENT long_event2 ON SCHEDULE EVERY 1 MINUTE DO INSERT INTO slow_event_test SELECT @@long_query_time, SLEEP(5);

CREATE EVENT long_event2 ON SCHEDULE EVERY 1 MINUTE DO INSERT INTO slow_event_test SELECT @@long_query_time, SLEEP(2);

"Sleep some more time than the actual event run will take"

"Check our table. Should see 2 rows"

SELECT * FROM slow_event_test;

slo_val	val

4	0

4	0

"Check slow log. Should see 1 row because 5 is over the threshold of 4 for GLOBAL, though under SESSION which is 10"

1	0

"Check slow log. Should see 1 row because 4 is over the threshold of 3 for GLOBAL, though under SESSION which is 10"

SELECT user_host, query_time, db, sql_text FROM mysql.slow_log;

user_host	query_time	db	sql_text

root[root] @ localhost [localhost]	SLEEPVAL	events_test	INSERT INTO slow_event_test SELECT @@long_query_time, SLEEP(5)

root[root] @ localhost [localhost]	SLEEPVAL	events_test	INSERT INTO slow_event_test SELECT @@long_query_time, SLEEP(2)

DROP EVENT long_event2;

SET GLOBAL  long_query_time =@old_global_long_query_time;

SET SESSION long_query_time =@old_session_long_query_time;