Comment 4 for bug 1308016

Revision history for this message
Nilnandan Joshi (nilnandan-joshi) wrote : Re: Duplicate UK values can be replicated under concurrent wokload

Tried to reproduce with Experimental Repo (PXC 5.6.19) and two different isolation levels (repeatable-read, read-committed)
But unable to get that error.

With Repeatable-read, it was working smoothly, while it was slow with read-committed and found below things in innodb status.

------------------------
LATEST DETECTED DEADLOCK
------------------------
2014-07-18 13:00:47 7f9681936700
*** (1) TRANSACTION:
TRANSACTION 1067388, ACTIVE 0 sec updating or deleting
mysql tables in use 1, locked 1
LOCK WAIT 3 lock struct(s), heap size 360, 2 row lock(s), undo log entries 1
MySQL thread id 2, OS thread handle 0x7f96819b8700, query id 7453285 localhost root update
*** (1) WAITING FOR THIS LOCK TO BE GRANTED:
RECORD LOCKS space id 6 page no 4 n bits 80 index `a` of table `test`.`t1` trx id 1067388 lock_mode X locks rec but not gap waiting
*** (2) TRANSACTION:
TRANSACTION 1067383, ACTIVE 0 sec inserting
mysql tables in use 1, locked 1
4 lock struct(s), heap size 1184, 3 row lock(s), undo log entries 2
MySQL thread id 4, OS thread handle 0x7f9681936700, query id 7453297 localhost root update
replace into t1(a,b,who,rep_count,trx_count,trx_started)
         values(floor(3*rand()), floor(3*rand()),
         me, @replace_count, @trx_count, @trx_started)
*** (2) HOLDS THE LOCK(S):
RECORD LOCKS space id 6 page no 4 n bits 80 index `a` of table `test`.`t1` trx id 1067383 lock_mode X locks rec but not gap
*** (2) WAITING FOR THIS LOCK TO BE GRANTED:
RECORD LOCKS space id 6 page no 3 n bits 72 index `PRIMARY` of table `test`.`t1` trx id 1067383 lock_mode X locks rec but not gap waiting
*** WE ROLL BACK TRANSACTION (1)
------------
TRANSACTIONS
------------
Trx id counter 1070024
Purge done for trx's n:o < 1070023 undo n:o < 0 state: running but idle
History list length 2200
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 0, not started
MySQL thread id 7, OS thread handle 0x7f96818f5700, query id 7474337 localhost root init
show engine innodb status
---TRANSACTION 1070017, not started flushing log
MySQL thread id 4, OS thread handle 0x7f9681936700, query id 7474306 localhost root closing tables
---TRANSACTION 1070022, not started flushing log
mysql tables in use 1, locked 1
MySQL thread id 2, OS thread handle 0x7f96819b8700, query id 7474336 localhost root query end
----------------------------
END OF INNODB MONITOR OUTPUT
============================