# include/concurrent.inc # # Concurrent tests for transactional storage engines, mainly in UPDATE's # Bug#3300 # Designed and tested by Sinisa Milivojevic, sinisa@mysql.com # # These variables have to be set before sourcing this script: # TRANSACTION ISOLATION LEVEL REPEATABLE READ # innodb_locks_unsafe_for_binlog 0 (default) or 1 (by # --innodb_locks_unsafe_for_binlog) # $engine_type storage engine to be tested # # Last update: # 2009-02-13 HH "Release_lock("hello")" is now also successful when delivering NULL, # replaced two sleeps by wait_condition. The last two "sleep 1" have not been # replaced as all tried wait conditions leaded to nondeterministic results, especially # to succeeding concurrent updates. To replace the sleeps there should be some time # planned (or internal knowledge of the server may help). # 2006-08-02 ML test refactored # old name was t/innodb_concurrent.test # main code went into include/concurrent.inc # 2008-06-03 KP test refactored; removed name locks, added comments. # renamed wrapper t/concurrent_innodb.test -> # t/concurrent_innodb_unsafelog.test # new wrapper t/concurrent_innodb_safelog.test # --source include/not_embedded.inc connection default; # # Show prerequisites for this test. # SELECT @@global.tx_isolation; SELECT @@global.innodb_locks_unsafe_for_binlog; # # When innodb_locks_unsafe_for_binlog is not set (zero), which is the # default, InnoDB takes "next-key locks"/"gap locks". This means it # locks the gap before the keys that it accessed to find the rows to # use for a statement. In this case we have to expect some more lock # wait timeouts in the tests below as if innodb_locks_unsafe_for_binlog # is set (non-zero). In the latter case no "next-key locks"/"gap locks" # are taken and locks on keys that do not match the WHERE conditon are # released. Hence less lock collisions occur. # We use the variable $keep_locks to set the expectations for # lock wait timeouts accordingly. # let $keep_locks= `SELECT NOT @@global.innodb_locks_unsafe_for_binlog`; --echo # keep_locks == $keep_locks # # Set up privileges and remove user level locks, if exist. # GRANT USAGE ON test.* TO mysqltest@localhost; # # Preparatory cleanup. # --disable_warnings drop table if exists t1; --enable_warnings --echo --echo ** --echo ** two UPDATE's running and both changing distinct result sets --echo ** --echo ** connection thread1 connect (thread1, localhost, mysqltest,,); connection thread1; --echo ** Set up table eval SET SESSION STORAGE_ENGINE = $engine_type; create table t1(eta int(11) not null, tipo int(11), c varchar(255)); insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"); insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"); insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc"); insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd"); insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee"); insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff"); insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg"); insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh"); insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii"); insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj"); insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk"); --echo ** Get user level lock (ULL) for thread 1 select get_lock("hello",10); --echo ** connection thread2 connect (thread2, localhost, mysqltest,,); connection thread2; --echo ** Start transaction for thread 2 begin; --echo ** Update will cause a table scan and a new ULL will --echo ** be created and blocked on the first row where tipo=11. send update t1 set eta=1+get_lock("hello",10)*0 where tipo=11; --echo ** connection thread1 connection thread1; let $wait_condition= select count(*)= 1 from information_schema.processlist where state= 'User lock'; --source include/wait_condition.inc --echo ** Start new transaction for thread 1 begin; --echo ** Update on t1 will cause a table scan which will be blocked because --echo ** the previously initiated table scan applied exclusive key locks on --echo ** all primary keys. --echo ** Not so if innodb_locks_unsafe_for_binlog is set. The locks that --echo ** do not match the WHERE condition are released. if ($keep_locks) { --error ER_LOCK_WAIT_TIMEOUT update t1 set eta=2 where tipo=22; } if (!$keep_locks) { update t1 set eta=2 where tipo=22; } --echo ** Release user level name lock from thread 1. This will cause the ULL --echo ** on thread 2 to end its wait. # Due to Bug#32782 User lock hash fails to find lock, which probably also cause Bug#39484 (main.concurrent_innodb_safelog fails sporadically) the success of the following # is also guaranteed for NULL. Replaced SELECT by DO (no result). DO release_lock("hello"); --echo ** Table is now updated with a new eta on tipo=22 for thread 1. select * from t1; --echo ** connection thread2 connection thread2; --echo ** Release the lock and collect result from update on thread 2 reap; # Due to Bug#32782 User lock hash fails to find lock, which probably also cause Bug#39484 (main.concurrent_innodb_safelog fails sporadically) the success of the following # is also guaranteed for NULL. Replaced SELECT by DO (no result). DO release_lock("hello"); --echo ** Table should have eta updates where tipo=11 but updates made by --echo ** thread 1 shouldn't be visible yet. select * from t1; --echo ** Sending commit on thread 2. commit; --echo ** connection thread1 connection thread1; --echo ** Make sure table reads didn't change yet on thread 1. select * from t1; --echo ** And send final commit on thread 1. commit; --echo ** Table should now be updated by both updates in the order of --echo ** thread 1,2. select * from t1; --echo ** connection thread2 connection thread2; --echo ** Make sure the output is similar for t1. select * from t1; --echo ** connection thread1 connection thread1; select * from t1; --echo ** connection default connection default; drop table t1; --echo --echo ** --echo ** two UPDATE's running and one changing result set --echo ** --echo ** connection thread1 #connect (thread1, localhost, mysqltest,,); connection thread1; --echo ** Set up table eval SET SESSION STORAGE_ENGINE = $engine_type; create table t1(eta int(11) not null, tipo int(11), c varchar(255)); insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"); insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"); insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc"); insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd"); insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee"); insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff"); insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg"); insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh"); insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii"); insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj"); insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk"); --echo ** Get ULL "hello" on thread 1 select get_lock("hello",10); --echo ** connection thread2 #connect (thread2, localhost, mysqltest,,); connection thread2; --echo ** Start transaction on thread 2 begin; --echo ** Update will cause a table scan. --echo ** This will cause a hang on the first row where tipo=1 until the --echo ** blocking ULL is released. send update t1 set eta=1+get_lock("hello",10)*0 where tipo=1; --echo ** connection thread1 connection thread1; let $wait_condition= select count(*)= 1 from information_schema.processlist where state= 'User lock'; --source include/wait_condition.inc --echo ** Start transaction on thread 1 begin; --echo ** Update on t1 will cause a table scan which will be blocked because --echo ** the previously initiated table scan applied exclusive key locks on --echo ** all primary keys. --echo ** Not so if innodb_locks_unsafe_for_binlog is set. The locks that --echo ** do not match the WHERE condition are released. if ($keep_locks) { --error ER_LOCK_WAIT_TIMEOUT update t1 set tipo=1 where tipo=2; } if (!$keep_locks) { update t1 set tipo=1 where tipo=2; } --echo ** Release ULL. This will release the next waiting ULL on thread 2. # Due to Bug#32782 User lock hash fails to find lock, which probably also cause Bug#39484 (main.concurrent_innodb_safelog fails sporadically)the success of the following # is also guaranteed for NULL. Replaced SELECT by DO (no result). DO release_lock("hello"); --echo ** The table should still be updated with updates for thread 1 only: select * from t1; --echo ** connection thread2 connection thread2; --echo ** Release the lock and collect result from thread 2: reap; # Due to Bug#32782 User lock hash fails to find lock, which probably also cause Bug#39484 (main.concurrent_innodb_safelog fails sporadically) the success of the following # is also guaranteed for NULL. Replaced SELECT by DO (no result). DO release_lock("hello"); --echo ** Seen from thread 2 the table should have been updated on four --echo ** places. select * from t1; commit; --echo ** connection thread1 connection thread1; --echo ** Thread 2 has committed but the result should remain the same for --echo ** thread 1 (updated on three places): select * from t1; commit; --echo ** After a commit the table should be merged with the previous --echo ** commit. --echo ** This select should show both updates: select * from t1; --echo ** connection thread2 connection thread2; select * from t1; --echo ** connection thread1 connection thread1; select * from t1; --echo ** connection default connection default; drop table t1; --echo --echo ** --echo ** One UPDATE and one INSERT .... Monty's test --echo ** --echo ** connection thread1 #connect (thread1, localhost, mysqltest,,); connection thread1; --echo ** Set up table eval SET SESSION STORAGE_ENGINE = $engine_type; create table t1 (a int not null, b int not null); insert into t1 values (1,1),(2,1),(3,1),(4,1); --echo ** Create ULL 'hello2' select get_lock("hello2",10); --echo ** connection thread2 #connect (thread2, localhost, mysqltest,,); connection thread2; --echo ** Begin a new transaction on thread 2 begin; --echo ** Update will create a table scan which creates a ULL where a=2; --echo ** this will hang waiting on thread 1. send update t1 set b=10+get_lock(concat("hello",a),10)*0 where a=2; --echo ** connection thread1 connection thread1; let $wait_condition= select count(*)= 1 from information_schema.processlist where state= 'User lock'; --source include/wait_condition.inc --echo ** Insert new values to t1 from thread 1; this created an implicit --echo ** commit since there are no on-going transactions. insert into t1 values (1,1); --echo ** Release the ULL (thread 2 updates will finish). # Due to Bug#32782 User lock hash fails to find lock, which probably also cause Bug#39484 (main.concurrent_innodb_safelog fails sporadically) the success of the following # is also guaranteed for NULL. Replaced SELECT by DO (no result). DO release_lock("hello2"); --echo ** ..but thread 1 will still see t1 as if nothing has happend: select * from t1; --echo ** connection thread2 connection thread2; --echo ** Collect results from thread 2 and release the lock. reap; # Due to Bug#32782 User lock hash fails to find lock, which probably also cause Bug#39484 (main.concurrent_innodb_safelog fails sporadically) the success of the following # is also guaranteed for NULL. Replaced SELECT by DO (no result). DO release_lock("hello2"); --echo ** The table should look like the original+updates for thread 2, --echo ** and consist of new rows: select * from t1; --echo ** Commit changes from thread 2 commit; --echo ** connection default connection default; drop table t1; --echo --echo ** --echo ** one UPDATE changing result set and SELECT ... FOR UPDATE --echo ** --echo ** connection thread1 #connect (thread1, localhost, mysqltest,,); connection thread1; --echo ** Set up table eval SET SESSION STORAGE_ENGINE = $engine_type; create table t1(eta int(11) not null, tipo int(11), c varchar(255)); insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"); insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"); insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc"); insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd"); insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee"); insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff"); insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg"); insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh"); insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii"); insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj"); insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk"); --echo ** connection thread2 #connect (thread2, localhost, mysqltest,,); connection thread2; --echo ** Begin a new transaction on thread 2 begin; --echo ** Select a range for update. select * from t1 where tipo=2 FOR UPDATE; --echo ** connection thread1 connection thread1; --echo ** Begin a new transaction on thread 1 begin; --echo ** Update the same range which is marked for update on thread 2; this --echo ** will hang because of row locks. --error ER_LOCK_WAIT_TIMEOUT update t1 set tipo=1 where tipo=2; --echo ** After the update the table will be unmodified because the previous --echo ** transaction failed and was rolled back. select * from t1; --echo ** connection thread2 connection thread2; --echo ** The table should look unmodified from thread 2. select * from t1; --echo ** Sending a commit should release the row locks and enable --echo ** thread 1 to complete the transaction. commit; --echo ** connection thread1 connection thread1; --echo ** Commit on thread 1. commit; --echo ** connection thread2 connection thread2; --echo ** The table should not have been changed. select * from t1; --echo ** connection thread1 connection thread1; --echo ** Even on thread 1: select * from t1; --echo ** connection default connection default; drop table t1; --echo --echo ** --echo ** one UPDATE not changing result set and SELECT ... FOR UPDATE --echo ** --echo ** connection thread1 #connect (thread1, localhost, mysqltest,,); connection thread1; --echo ** Set up table eval SET SESSION STORAGE_ENGINE = $engine_type; create table t1(eta int(11) not null, tipo int(11), c varchar(255)); insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"); insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"); insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc"); insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd"); insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee"); insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff"); insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg"); insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh"); insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii"); insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj"); insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk"); --echo ** connection thread2 #connect (thread2, localhost, mysqltest,,); connection thread2; --echo ** Starting new transaction on thread 2. begin; --echo ** Starting SELECT .. FOR UPDATE select * from t1 where tipo=2 FOR UPDATE; --echo ** connection thread1 connection thread1; --echo --echo ** Starting new transaction on thread 1 begin; --echo ** Updating single row using a table scan. This will time out --echo ** because of ongoing transaction on thread 1 holding lock on --echo ** all primary keys in the scan. --echo ** Not so if innodb_locks_unsafe_for_binlog is set. The locks that --echo ** do not match the WHERE condition are released. if ($keep_locks) { --error ER_LOCK_WAIT_TIMEOUT update t1 set tipo=11 where tipo=22; } if (!$keep_locks) { update t1 set tipo=11 where tipo=22; } --echo ** After the time out the transaction is aborted; no rows should --echo ** have changed. select * from t1; --echo ** connection thread2 connection thread2; --echo ** The same thing should hold true for the transaction on --echo ** thread 2 select * from t1; send commit; --echo ** connection thread1 connection thread1; commit; --echo ** connection thread2 connection thread2; --echo ** Even after committing: reap; select * from t1; --echo ** connection thread1 connection thread1; select * from t1; --echo ** connection default connection default; drop table t1; --echo --echo ** --echo ** two SELECT ... FOR UPDATE --echo ** --echo ** connection thread1 #connect (thread1, localhost, mysqltest,,); connection thread1; --echo ** Set up table eval SET SESSION STORAGE_ENGINE = $engine_type; create table t1(eta int(11) not null, tipo int(11), c varchar(255)); insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"); insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"); insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc"); insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd"); insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee"); insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff"); insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg"); insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh"); insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii"); insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj"); insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk"); --echo ** connection thread2 #connect (thread2, localhost, mysqltest,,); connection thread2; --echo ** Begin a new transaction on thread 2 begin; select * from t1 where tipo=2 FOR UPDATE; --echo ** connection thread1 connection thread1; --echo ** Begin a new transaction on thread 1 begin; --echo ** Selecting a range for update by table scan will be blocked --echo ** because of on-going transaction on thread 2. --error ER_LOCK_WAIT_TIMEOUT select * from t1 where tipo=1 FOR UPDATE; --echo ** connection thread2 connection thread2; --echo ** Table will be unchanged and the select command will not be --echo ** blocked: select * from t1; --echo ** Commit transacton on thread 2. commit; --echo ** connection thread1 connection thread1; --echo ** Commit transaction on thread 1. commit; --echo ** connection thread2 connection thread2; --echo ** Make sure table isn't blocked on thread 2: select * from t1; --echo ** connection thread1 connection thread1; --echo ** Make sure table isn't blocked on thread 1: select * from t1; --echo ** connection default connection default; drop table t1; --echo --echo ** --echo ** one UPDATE changing result set and DELETE --echo ** --echo ** connection thread1 #connect (thread1, localhost, mysqltest,,); connection thread1; --echo ** Set up table eval SET SESSION STORAGE_ENGINE = $engine_type; create table t1(eta int(11) not null, tipo int(11), c varchar(255)); insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"); insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"); insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc"); insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd"); insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee"); insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff"); insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg"); insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh"); insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii"); insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj"); insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk"); --echo ** connection thread2 #connect (thread2, localhost, mysqltest,,); connection thread2; begin; send delete from t1 where tipo=2; # The sleep has not been replaced as all tried wait conditions leaded to sporadically # succeding update in the following thread. Also the used status variables '%lock%' and # 'innodb_deleted_rows' and infos in processlist where not sucessful. sleep 1; --echo ** connection thread1 connection thread1; begin; --error ER_LOCK_WAIT_TIMEOUT update t1 set tipo=1 where tipo=2; select * from t1; --echo ** connection thread2 connection thread2; reap; select * from t1; send commit; --echo ** connection thread1 connection thread1; commit; --echo ** connection thread2 connection thread2; reap; select * from t1; --echo ** connection thread1 connection thread1; select * from t1; --echo ** connection default connection default; drop table t1; --echo --echo ** --echo ** one UPDATE not changing result set and DELETE --echo ** --echo ** connection thread1 #connect (thread1, localhost, mysqltest,,); connection thread1; --echo ** Set up table eval SET SESSION STORAGE_ENGINE = $engine_type; create table t1(eta int(11) not null, tipo int(11), c varchar(255)); insert into t1 values (7,7, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"); insert into t1 values (8,8, "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"); insert into t1 values (10,1,"ccccccccccccccccccccccccccccccccccccccccccc"); insert into t1 values (20,2,"ddddddddddddddddddddddddddddddddddddddddddd"); insert into t1 values (30,1,"eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee"); insert into t1 values (40,2,"fffffffffffffffffffffffffffffffffffffffffff"); insert into t1 values (50,1,"ggggggggggggggggggggggggggggggggggggggggggg"); insert into t1 values (60,2,"hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh"); insert into t1 values (70,1,"iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii"); insert into t1 values (80,22,"jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj"); insert into t1 values (90,11,"kkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk"); --echo ** connection thread2 #connect (thread2, localhost, mysqltest,,); connection thread2; begin; send delete from t1 where tipo=2; # The sleep has not been replaced as all tried wait conditions leaded to sporadically # succeding update in the following thread. Also the used status variables '%lock%' and # 'innodb_deleted_rows' and infos in processlist where not sucessful. sleep 1; --echo ** connection thread1 connection thread1; begin; --echo ** Update on t1 will cause a table scan which will be blocked because --echo ** the previously initiated table scan applied exclusive key locks on --echo ** all primary keys. --echo ** Not so if innodb_locks_unsafe_for_binlog is set. The locks that --echo ** do not match the WHERE condition are released. if ($keep_locks) { --error ER_LOCK_WAIT_TIMEOUT update t1 set tipo=1 where tipo=22; } if (!$keep_locks) { update t1 set tipo=1 where tipo=22; } select * from t1; --echo ** connection thread2 connection thread2; reap; select * from t1; send commit; --echo ** connection thread1 connection thread1; commit; --echo ** connection thread2 connection thread2; reap; select * from t1; --echo ** connection thread1 connection thread1; select * from t1; --echo ** Cleanup connection thread1; disconnect thread1; --source include/wait_until_disconnected.inc --echo ** connection thread2 connection thread2; disconnect thread2; --source include/wait_until_disconnected.inc --echo ** connection default connection default; drop table t1; drop user mysqltest@localhost;