MDEV 4427: query timeouts

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

Author: montywi

.gitignore

@@ -75,6 +75,7 @@ mysql-test/mtr
 mysql-test/mysql-test-run
 mysql-test/var/
 mysys/thr_lock
+mysys/thr_timer
 packaging/rpm-oel/mysql.spec
 packaging/rpm-uln/mysql.10.0.11.spec
 packaging/solaris/postinstall-solaris

include/thr_timer.h

@@ -0,0 +1,45 @@
+/* Copyright (c) 2012 Monty Program Ab
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 or later of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
+
+/* Prototypes when using thr_timer functions */
+
+#ifndef _thr_timer_h
+#define _thr_timer_h
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+typedef struct st_timer {
+  struct timespec expire_time;
+  my_bool expired;
+  uint index_in_queue;
+  void (*func)(void*);
+  void *func_arg;
+} thr_timer_t;
+
+/* Main functions for library */
+my_bool init_thr_timer(uint init_size_for_timer_queue);
+void end_thr_timer();
+
+/* Functions for handling one timer */
+void thr_timer_init(thr_timer_t *timer_data, void(*function)(void*),
+                    void *arg);
+my_bool thr_timer_settime(thr_timer_t *timer_data, ulonglong microseconds);
+void    thr_timer_end(thr_timer_t *timer_data);
+
+#ifdef	__cplusplus
+}
+#endif /* __cplusplus */
+#endif /* _thr_timer_h */

mysql-test/r/grant.result

@@ -58,6 +58,7 @@ authentication_string
 password_expired	N
 is_role	N
 default_role	
+max_statement_time	0.000000
 show grants for mysqltest_1@localhost;
 Grants for mysqltest_1@localhost
 GRANT USAGE ON *.* TO 'mysqltest_1'@'localhost' REQUIRE CIPHER 'EDH-RSA-DES-CBC3-SHA'
@@ -85,7 +86,7 @@ delete from mysql.user where user='mysqltest_1';
 flush privileges;
 delete from mysql.user where user='mysqltest_1';
 flush privileges;
-grant usage on *.* to mysqltest_1@localhost with max_queries_per_hour 10;
+grant usage on *.* to mysqltest_1@localhost with max_queries_per_hour 10 max_statement_time 60;
 select * from mysql.user where user="mysqltest_1";
 Host	localhost
 User	mysqltest_1
@@ -132,10 +133,11 @@ authentication_string
 password_expired	N
 is_role	N
 default_role	
+max_statement_time	60.000000
 show grants for mysqltest_1@localhost;
 Grants for mysqltest_1@localhost
-GRANT USAGE ON *.* TO 'mysqltest_1'@'localhost' WITH MAX_QUERIES_PER_HOUR 10
-grant usage on *.* to mysqltest_1@localhost with max_updates_per_hour 20 max_connections_per_hour 30;
+GRANT USAGE ON *.* TO 'mysqltest_1'@'localhost' WITH MAX_QUERIES_PER_HOUR 10 MAX_STATEMENT_TIME 60.000000
+grant usage on *.* to mysqltest_1@localhost with max_updates_per_hour 20 max_connections_per_hour 30 max_statement_time 0;
 select * from mysql.user where user="mysqltest_1";
 Host	localhost
 User	mysqltest_1
@@ -182,6 +184,7 @@ authentication_string
 password_expired	N
 is_role	N
 default_role	
+max_statement_time	0.000000
 show grants for mysqltest_1@localhost;
 Grants for mysqltest_1@localhost
 GRANT USAGE ON *.* TO 'mysqltest_1'@'localhost' WITH MAX_QUERIES_PER_HOUR 10 MAX_UPDATES_PER_HOUR 20 MAX_CONNECTIONS_PER_HOUR 30

mysql-test/r/max_statement_time.result

@@ -0,0 +1,147 @@
+
+# Test the MAX_STATEMENT_TIME option.
+
+SET @@MAX_STATEMENT_TIME=2;
+select @@max_statement_time;
+@@max_statement_time
+2.000000
+SELECT SLEEP(1);
+SLEEP(1)
+0
+SELECT SLEEP(3);
+SLEEP(3)
+1
+SET @@MAX_STATEMENT_TIME=0;
+SELECT SLEEP(1);
+SLEEP(1)
+0
+SHOW STATUS LIKE "max_statement_time_exceeded";
+Variable_name	Value
+Max_statement_time_exceeded	1
+CREATE TABLE t1 (a INT, b VARCHAR(300)) engine=myisam;
+INSERT INTO t1 VALUES (1, 'string');
+SELECT 0;
+0
+0
+
+# Test the MAX_STATEMENT_TIME option with SF (should have no effect).
+
+CREATE PROCEDURE p1()
+BEGIN
+declare tmp int;
+SET @@MAX_STATEMENT_TIME=0.0001;
+SELECT COUNT(*) INTO tmp FROM t1 WHERE b LIKE '%z%';
+SET @@MAX_STATEMENT_TIME=0;
+END|
+CREATE PROCEDURE p2()
+BEGIN
+SET @@MAX_STATEMENT_TIME=5;
+END|
+SELECT @@MAX_STATEMENT_TIME;
+@@MAX_STATEMENT_TIME
+0.000000
+CALL p1();
+CALL p2();
+SELECT @@MAX_STATEMENT_TIME;
+@@MAX_STATEMENT_TIME
+5.000000
+SET @@MAX_STATEMENT_TIME=0;
+DROP PROCEDURE p1;
+DROP PROCEDURE p2;
+DROP TABLE t1;
+
+# MAX_STATEMENT_TIME account resource
+
+GRANT USAGE ON *.* TO user1@localhost WITH MAX_STATEMENT_TIME 1.005;
+# con1
+SELECT @@max_statement_time;
+@@max_statement_time
+1.005000
+# restart and reconnect
+set @global.userstat=1;
+SELECT @@global.max_statement_time,@@session.max_statement_time;
+@@global.max_statement_time	@@session.max_statement_time
+0.000000	1.005000
+select sleep(100);
+sleep(100)
+1
+SHOW STATUS LIKE "max_statement_time_exceeded";
+Variable_name	Value
+Max_statement_time_exceeded	1
+show grants for user1@localhost;
+Grants for user1@localhost
+GRANT USAGE ON *.* TO 'user1'@'localhost' WITH MAX_STATEMENT_TIME 1.005000
+set @global.userstat=0;
+DROP USER user1@localhost;
+
+# MAX_STATEMENT_TIME status variables.
+
+flush status;
+SET @@max_statement_time=0;
+SELECT CONVERT(VARIABLE_VALUE, UNSIGNED) INTO @time_exceeded
+FROM INFORMATION_SCHEMA.GLOBAL_STATUS
+WHERE VARIABLE_NAME = 'max_statement_time_exceeded';
+SET @@max_statement_time=0.5;
+SELECT SLEEP(2);
+SLEEP(2)
+1
+SHOW STATUS LIKE '%timeout%';
+Variable_name	Value
+Ssl_default_timeout	0
+Ssl_session_cache_timeouts	0
+SET @@max_statement_time=0;
+# Ensure that the counters for:
+# - statements that exceeded their maximum execution time
+# are incremented.
+SELECT 1 AS STATUS FROM INFORMATION_SCHEMA.GLOBAL_STATUS
+WHERE VARIABLE_NAME = 'max_statement_time_exceeded'
+        AND CONVERT(VARIABLE_VALUE, UNSIGNED) > @time_exceeded;
+STATUS
+1
+
+# Check that the appropriate error status is set.
+
+CREATE TABLE t1 (a INT) ENGINE=InnoDB;
+INSERT INTO t1 VALUES (1);
+START TRANSACTION;
+SELECT * FROM t1 FOR UPDATE;
+a
+1
+SET @@SESSION.max_statement_time = 0.5;
+UPDATE t1 SET a = 2;
+ERROR 70100: Query execution was interrupted (max_statement_time exceeded)
+SHOW WARNINGS;
+Level	Code	Message
+Error	1967	Query execution was interrupted (max_statement_time exceeded)
+ROLLBACK;
+DROP TABLE t1;
+
+# Test interaction with lock waits.
+
+CREATE TABLE t1 (a INT) ENGINE=InnoDB;
+INSERT INTO t1 VALUES (1);
+SET @@SESSION.max_statement_time= 0.5;
+LOCK TABLES t1 WRITE;
+SELECT @@SESSION.max_statement_time;
+@@SESSION.max_statement_time
+0.500000
+LOCK TABLES t1 READ;
+ERROR 70100: Query execution was interrupted (max_statement_time exceeded)
+UNLOCK TABLES;
+BEGIN;
+SELECT * FROM t1;
+a
+1
+ALTER TABLE t1 ADD COLUMN b INT;
+ERROR 70100: Query execution was interrupted (max_statement_time exceeded)
+ROLLBACK;
+SELECT GET_LOCK('lock', 1);
+GET_LOCK('lock', 1)
+1
+SELECT GET_LOCK('lock', 1);
+GET_LOCK('lock', 1)
+NULL
+SELECT RELEASE_LOCK('lock');
+RELEASE_LOCK('lock')
+1
+DROP TABLE t1;

mysql-test/r/mysqld--help.result

@@ -422,6 +422,11 @@ The following options may be given as the first argument:
  value are used; the rest are ignored)
  --max-sp-recursion-depth[=#] 
  Maximum stored procedure recursion depth
+ --max-statement-time=# 
+ A SELECT query that have taken more than
+ max_statement_time seconds will be aborted. The argument
+ will be treated as a decimal value with microsecond
+ precision.  A value of 0 (default) means no timeout
  --max-tmp-tables=#  Maximum number of temporary tables a client can keep open
  at a time
  --max-user-connections=# 
@@ -1196,6 +1201,7 @@ max-relay-log-size 1073741824
 max-seeks-for-key 18446744073709551615
 max-sort-length 1024
 max-sp-recursion-depth 0
+max-statement-time 0
 max-tmp-tables 32
 max-user-connections 0
 max-write-lock-count 18446744073709551615

mysql-test/r/ps.result

@@ -1202,13 +1202,13 @@ SET @aux= "SELECT COUNT(*)
 prepare my_stmt from @aux;
 execute my_stmt;
 COUNT(*)
-45
+46
 execute my_stmt;
 COUNT(*)
-45
+46
 execute my_stmt;
 COUNT(*)
-45
+46
 deallocate prepare my_stmt;
 drop procedure if exists p1|
 drop table if exists t1|

mysql-test/r/status_user.result

@@ -25,6 +25,7 @@ DENIED_CONNECTIONS	bigint(21)	NO		0
 LOST_CONNECTIONS	bigint(21)	NO		0	
 ACCESS_DENIED	bigint(21)	NO		0	
 EMPTY_QUERIES	bigint(21)	NO		0	
+MAX_STATEMENT_TIME_EXCEEDED	bigint(21)	NO		0	
 show columns from information_schema.user_statistics;
 Field	Type	Null	Key	Default	Extra
 USER	varchar(128)	NO			
@@ -50,6 +51,7 @@ DENIED_CONNECTIONS	bigint(21)	NO		0
 LOST_CONNECTIONS	bigint(21)	NO		0	
 ACCESS_DENIED	bigint(21)	NO		0	
 EMPTY_QUERIES	bigint(21)	NO		0	
+MAX_STATEMENT_TIME_EXCEEDED	bigint(21)	NO		0	
 show columns from information_schema.index_statistics;
 Field	Type	Null	Key	Default	Extra
 TABLE_SCHEMA	varchar(192)	NO			

mysql-test/r/system_mysql_db.result

@@ -131,6 +131,7 @@ user	CREATE TABLE `user` (
   `password_expired` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
   `is_role` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
   `default_role` char(80) COLLATE utf8_bin NOT NULL DEFAULT '',
+  `max_statement_time` decimal(12,6) NOT NULL DEFAULT '0.000000',
   PRIMARY KEY (`Host`,`User`)
 ) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_bin COMMENT='Users and global privileges'
 show create table func;

mysql-test/r/system_mysql_db_fix40123.result

@@ -131,6 +131,7 @@ user	CREATE TABLE `user` (
   `password_expired` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
   `is_role` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
   `default_role` char(80) COLLATE utf8_bin NOT NULL DEFAULT '',
+  `max_statement_time` decimal(12,6) NOT NULL DEFAULT '0.000000',
   PRIMARY KEY (`Host`,`User`)
 ) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_bin COMMENT='Users and global privileges'
 show create table func;

mysql-test/r/system_mysql_db_fix50030.result

@@ -131,6 +131,7 @@ user	CREATE TABLE `user` (
   `password_expired` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
   `is_role` enum('N','Y') CHARACTER SET utf8 NOT NULL DEFAULT 'N',
   `default_role` char(80) COLLATE utf8_bin NOT NULL DEFAULT '',
+  `max_statement_time` decimal(12,6) NOT NULL DEFAULT '0.000000',
   PRIMARY KEY (`Host`,`User`)
 ) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_bin COMMENT='Users and global privileges'
 show create table func;