mariadb/mysql-test/t/lock_multi.test
ingo@mysql.com d27a15a81c Bug#16986 - Deadlock condition with MyISAM tables
Addendum fixes after changing the condition variable
for the global read lock.

The stress test suite revealed some deadlocks. Some were
related to the new condition variable (COND_global_read_lock)
and some were general problems with the global read lock.

It is now necessary to signal COND_global_read_lock whenever 
COND_refresh is signalled.

We need to wait for the release of a global read lock if one 
is set before every operation that requires a write lock.
But we must not wait if we have locked tables by LOCK TABLES.
After setting a global read lock a thread waits until all
write locks are released.
2006-06-26 19:14:35 +02:00

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# This test doesn't work with the embedded version as this code
# assumes that one query is running while we are doing queries on
# a second connection.
# This would work if mysqltest run would be threaded and handle each
# connection in a separate thread.
#
-- source include/not_embedded.inc
--disable_warnings
drop table if exists t1,t2;
--enable_warnings
# Test to see if select will get the lock ahead of low priority update
connect (locker,localhost,root,,);
connect (reader,localhost,root,,);
connect (writer,localhost,root,,);
connection locker;
create table t1(n int);
insert into t1 values (1);
lock tables t1 write;
connection writer;
send update low_priority t1 set n = 4;
connection reader;
--sleep 2
send select n from t1;
connection locker;
--sleep 2
unlock tables;
connection writer;
reap;
connection reader;
reap;
drop table t1;
connection locker;
create table t1(n int);
insert into t1 values (1);
lock tables t1 read;
connection writer;
send update low_priority t1 set n = 4;
connection reader;
--sleep 2
send select n from t1;
connection locker;
--sleep 2
unlock tables;
connection writer;
reap;
connection reader;
reap;
drop table t1;
#
# Test problem when using locks with multi-updates
# It should not block when multi-update is reading on a read-locked table
#
connection locker;
create table t1 (a int, b int);
create table t2 (c int, d int);
insert into t1 values(1,1);
insert into t1 values(2,2);
insert into t2 values(1,2);
lock table t1 read;
connection writer;
--sleep 2
send update t1,t2 set c=a where b=d;
connection reader;
--sleep 2
select c from t2;
connection writer;
reap;
connection locker;
drop table t1;
drop table t2;
#
# Test problem when using locks on many tables and droping a table that
# is to-be-locked by another thread
#
connection locker;
create table t1 (a int);
create table t2 (a int);
lock table t1 write, t2 write;
connection reader;
send insert t1 select * from t2;
connection locker;
drop table t2;
connection reader;
--error 1146
reap;
connection locker;
drop table t1;
# End of 4.1 tests
#
# BUG#9998 - MySQL client hangs on USE "database"
#
create table t1(a int);
lock tables t1 write;
connection reader;
show columns from t1;
connection locker;
unlock tables;
drop table t1;
#
# Bug#19815 - CREATE/RENAME/DROP DATABASE can deadlock on a global read lock
#
connect (con1,localhost,root,,);
connect (con2,localhost,root,,);
#
connection con1;
CREATE DATABASE mysqltest_1;
FLUSH TABLES WITH READ LOCK;
#
# With bug in place: acquire LOCK_mysql_create_table and
# wait in wait_if_global_read_lock().
connection con2;
send DROP DATABASE mysqltest_1;
--sleep 1
#
# With bug in place: try to acquire LOCK_mysql_create_table...
# When fixed: Reject dropping db because of the read lock.
connection con1;
--error ER_CANT_UPDATE_WITH_READLOCK
DROP DATABASE mysqltest_1;
UNLOCK TABLES;
#
connection con2;
reap;
#
connection default;
disconnect con1;
disconnect con2;
# This must have been dropped by connection 2 already,
# which waited until the global read lock was released.
--error ER_DB_DROP_EXISTS
DROP DATABASE mysqltest_1;
#
# Bug#16986 - Deadlock condition with MyISAM tables
#
connection locker;
use mysql;
LOCK TABLES columns_priv WRITE, db WRITE, host WRITE, user WRITE;
FLUSH TABLES;
--sleep 1
#
connection reader;
use mysql;
#NOTE: This must be a multi-table select, otherwise the deadlock will not occur
send SELECT user.Select_priv FROM user, db WHERE user.user = db.user LIMIT 1;
--sleep 1
#
connection locker;
# Make test case independent from earlier grants.
--replace_result "Table is already up to date" "OK"
OPTIMIZE TABLES columns_priv, db, host, user;
UNLOCK TABLES;
#
connection reader;
reap;
use test;
#
connection locker;
use test;
#
connection default;
#
# Test if CREATE TABLE with LOCK TABLE deadlocks.
#
connection writer;
CREATE TABLE t1 (c1 int);
LOCK TABLE t1 WRITE;
#
# This waits until t1 is unlocked.
connection locker;
send FLUSH TABLES WITH READ LOCK;
--sleep 1
#
# This must not block.
connection writer;
CREATE TABLE t2 (c1 int);
UNLOCK TABLES;
#
# This awakes now.
connection locker;
reap;
UNLOCK TABLES;
#
connection default;
DROP TABLE t1, t2;
#
# Test if CREATE TABLE SELECT with LOCK TABLE deadlocks.
#
connection writer;
CREATE TABLE t1 (c1 int);
LOCK TABLE t1 WRITE;
#
# This waits until t1 is unlocked.
connection locker;
send FLUSH TABLES WITH READ LOCK;
--sleep 1
#
# This must not block.
connection writer;
--error 1100
CREATE TABLE t2 AS SELECT * FROM t1;
UNLOCK TABLES;
#
# This awakes now.
connection locker;
reap;
UNLOCK TABLES;
#
connection default;
DROP TABLE t1;
#
# Bug #17264: MySQL Server freeze
#
connection locker;
create table t1 (f1 int(12) unsigned not null auto_increment, primary key(f1)) engine=innodb;
lock tables t1 write;
connection writer;
--sleep 2
delimiter //;
send alter table t1 auto_increment=0; alter table t1 auto_increment=0; alter table t1 auto_increment=0; alter table t1 auto_increment=0; alter table t1 auto_increment=0; //
delimiter ;//
connection reader;
--sleep 2
delimiter //;
send alter table t1 auto_increment=0; alter table t1 auto_increment=0; alter table t1 auto_increment=0; alter table t1 auto_increment=0; alter table t1 auto_increment=0; //
delimiter ;//
connection locker;
--sleep 2
unlock tables;
connection writer;
reap;
connection reader;
reap;
connection locker;
drop table t1;
# End of 5.0 tests