MySQL patches by Codership

  1. Bug #1308016
  2. Comment #12

Comment 12 for bug 1308016

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

Hi Raghu,

I have tried to reproduce the same with SP testcase + PS 5.6.21/MySQL 5.6.21 community + 3 parallel sessions. but I could not able to reproduce it.

On PS 5.6.21,

mysql> show processlist;
+----+------+-----------+------+---------+------+-----------+------------------------------------------------------------------------------------------------------+-----------+---------------+
| Id | User | Host | db | Command | Time | State | Info | Rows_sent | Rows_examined |
 +----+------+-----------+------+---------+------+-----------+------------------------------------------------------------------------------------------------------+-----------+---------------+
| 45 | root | localhost | test | Query | 0 | init | show processlist | 0 | 0 |
| 46 | root | localhost | test | Query | 0 | query end | replace into t1(a,b,who,rep_count,trx_count,trx_started)
          values(floor(3*rand()), floor(3*ra | 224 | 29262 |
| 48 | root | localhost | test | Sleep | 19 | | NULL | 0 | 0 |
| 53 | root | localhost | test | Query | 0 | update | replace into t1(a,b,who,rep_count,trx_count,trx_started)
          values(floor(3*rand()), floor(3*ra | 150 | 17067 |
| 54 | root | localhost | test | Query | 0 | query end | replace into t1(a,b,who,rep_count,trx_count,trx_started)
          values(floor(3*rand()), floor(3*ra | 179 | 25116 |
+----+------+-----------+------+---------+------+-----------+------------------------------------------------------------------------------------------------------+-----------+---------------+
5 rows in set (0.00 sec)

On MySQL 5.6.21,

mysql> show processlist;
+----+------+-----------+------+---------+------+-----------+------------------------------------------------------------------------------------------------------+
| Id | User | Host | db | Command | Time | State | Info |
 +----+------+-----------+------+---------+------+-----------+------------------------------------------------------------------------------------------------------+
| 1 | root | localhost | test | Sleep | 109 | | NULL |
| 2 | root | localhost | test | Query | 0 | init | show processlist |
| 3 | root | localhost | test | Query | 0 | query end | replace into t1(a,b,who,rep_count,trx_count,trx_started)
          values(floor(3*rand()), floor(3*ra |
| 4 | root | localhost | test | Query | 0 | query end | replace into t1(a,b,who,rep_count,trx_count,trx_started)
          values(floor(3*rand()), floor(3*ra |
| 5 | root | localhost | test | Query | 0 | update | replace into t1(a,b,who,rep_count,trx_count,trx_started)
          values(floor(3*rand()), floor(3*ra |
+----+------+-----------+------+---------+------+-----------+------------------------------------------------------------------------------------------------------+
5 rows in set (0.00 sec)