Test tokudb.locks-select-update-3 is unstable

[Laurynas Biveinis]

On 5.6 trunk, ASan build:

tokudb.locks-select-update-3 w3 [ fail ]
        Test ended at 2017-02-06 14:16:01

CURRENT_TEST: tokudb.locks-select-update-3
mysqltest: At line 27: query 'reap' failed: 1205: Lock wait timeout exceeded; try restarting transaction

The result from queries just before the failure was:
SET DEFAULT_STORAGE_ENGINE='tokudb';
drop table if exists t;
create table t (a int primary key, b int);
insert into t values (1,0);
set session transaction isolation level read committed;
begin;
select * from t where a=1 for update;
a b
1 0
update t set b=b+1 where a=1;
set session transaction isolation level read committed;
begin;
select * from t where a=1 for update;
commit;
safe_process[8432]: Child process: 8434, exit: 1

Server [mysqld.1 - pid: 8152, winpid: 8152] log:
Server log from this test:
----------SERVER LOG START-----------
----------SERVER LOG END-------------

[Elena Stepanova (elenst)]

We are getting the same failure, although rarely. If a machine or a build is very slow, the part where the test switched to the default connection, runs SELECT and COMMIT, and switches back, can take time, and since the default TokuDB lock timeout is only 4 seconds, the timeout occurs. Since the logic of the test is unrelated to the timeout, it makes sense just to set it to a higher value:

diff --git a/storage/tokudb/mysql-test/tokudb/r/locks-select-update-3.result b/storage/tokudb/mysql-test/tokudb/r/locks-select-update-3.result
index 8b31bf5..c1f05cd 100644
--- a/storage/tokudb/mysql-test/tokudb/r/locks-select-update-3.result
+++ b/storage/tokudb/mysql-test/tokudb/r/locks-select-update-3.result
@@ -8,6 +8,7 @@ select * from t where a=1 for update;
 a b
 1 0
 update t set b=b+1 where a=1;
+set session tokudb_lock_timeout= 60000;
 set session transaction isolation level read committed;
 begin;
 select * from t where a=1 for update;
diff --git a/storage/tokudb/mysql-test/tokudb/t/locks-select-update-3.test b/storage/tokudb/mysql-test/tokudb/t/locks-select-update-3.test
index a563f06..5b54fa7 100644
--- a/storage/tokudb/mysql-test/tokudb/t/locks-select-update-3.test
+++ b/storage/tokudb/mysql-test/tokudb/t/locks-select-update-3.test
@@ -15,6 +15,7 @@ select * from t where a=1 for update;
 # t2 update
 update t set b=b+1 where a=1;
 connect(conn1,localhost,root);
+set session tokudb_lock_timeout= 60000;
 set session transaction isolation level read committed;
 begin;
 # t2 select for update, should hang until t1 commits

[Sveta Smirnova (svetasmirnova)]

At the other side this can be easily reproduced on demand if run test as

./mtr --suite=tokudb locks-select-update-3 --mysqld=--tokudb_lock_timeout=50

Repeatable with 5.7 as well

[George Ormond Lorch III (gl-az)]

Tracking in https://jira.percona.com/browse/TDB-44, please login there to Percona JIRA and 'watch' for future updates. Marking it as opinion here as there is no other accurate matching state.

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PS-2235