Details
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Technical task
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Status: Closed (View Workflow)
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Minor
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Resolution: Fixed
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None
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None
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None
Description
One connection locked a row, another connection attempts to update the row and starts waiting for the lock. Killing the waiting query has no effect until the wait timeout is exceeded, and only after that the query ends with 'execution interrupted' (rather than 'timeout exceeded').
In the test below we execute the described scenario with leveldb_lock_wait_timeout set to 5. The connection which killed the query waits for 1 second and then checks the processlist – the query is still there, and the state is 'updating', not 'killed'. When the query ends, we can see from now() values that it took full 5 seconds.
For InnoDB it works as expected, the query gets killed.
Test output:
create table t1 (pk int primary key, a int) engine=LevelDB; |
insert into t1 values (1,10),(2,20); |
begin; |
update t1 set a = 100 where pk = 1; |
connect con1,localhost,root,,; |
set leveldb_lock_wait_timeout=5; |
select now(); |
now()
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2013-01-16 17:44:47
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update t1 set a = 1000 where pk = 1;; |
connect con2,localhost,root,,; |
kill query 3;
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show processlist;
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Id User Host db Command Time State Info |
4 root localhost test Query 0 init show processlist
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3 root localhost test Query 1 updating update t1 set a = 1000 where pk = 1 |
2 root localhost test Sleep 1 NULL |
connection con1; |
ERROR 70100: Query execution was interrupted
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select now(); |
now()
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2013-01-16 17:44:52
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connection default; |
commit; |
Test case:
--enable_connect_log
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create table t1 (pk int primary key, a int) engine=LevelDB; |
insert into t1 values (1,10),(2,20); |
begin; |
update t1 set a = 100 where pk = 1; |
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--connect (con1,localhost,root,,)
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--let $con1_id = `SELECT CONNECTION_ID()`
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set leveldb_lock_wait_timeout=5; |
select now(); |
--send update t1 set a = 1000 where pk = 1;
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--connect (con2,localhost,root,,)
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eval kill query $con1_id;
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--sleep 1
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show processlist;
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--connection con1
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--error ER_QUERY_INTERRUPTED
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--reap
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select now(); |
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--connection default
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commit; |
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revision-id: psergey@askmonty.org-20130115181447-1jfr200qcuqzp1sr
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revno: 4495
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branch-nick: mysql-5.6-leveldb
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