percona-discussion team mailing list archive

[Vadim Tkachenko <vadim@xxxxxxxxxxx>]

MARK ,


This is rw_lock, so no output in SHOW MUTEX STATUS.

But in SHOW INNODB STATUS it fills several screens in output.



MARK CALLAGHAN wrote:
> On Thu, Apr 9, 2009 at 11:55 AM, Evgeniy Stepchenko
> <evgeny.stepchenko@xxxxxxxxxxx> wrote:
>> ** Changed in: percona-xtradb
>>   Importance: Undecided => Medium
>>
>> ** Changed in: percona-patches
>>   Importance: Undecided => Medium
>>
>> --
>> Adaptive search scalability
>> https://bugs.launchpad.net/bugs/331659
>> You received this bug notification because you are a member of Percona
>> developers, which is the registrant for Percona patches.
>>
>> Status in Patches for MySQL by Percona: New
>> Status in Percona XtraDB Storage Engine for MySQL: New
>>
>> Bug description:
>> During some workloads I see a lot of output
>> --Thread 1164450128 has waited at btr0sea.c line 1383 for 0.00 seconds the semaphore:
>> X-lock on RW-latch at 0x2aaaac50e0b8 created in file btr0sea.c line 139
>> a writer (thread id 1164450128) has reserved it in mode  wait exclusive
>>  number of readers 1, waiters flag 1
>>  Last time read locked in file btr0sea.c line 746
>>  Last time write locked in file btr0sea.c line 1383
>>  though the waits are very small though -- 0.00
>>
>> What we can do there ?
> 
> Does SHOW MUTEX STATUS report a lot of contention for it?
> 
>> _______________________________________________
>> Mailing list: https://launchpad.net/~percona-discussion
>> Post to     : percona-discussion@xxxxxxxxxxxxxxxxxxx
>> Unsubscribe : https://launchpad.net/~percona-discussion
>> More help   : https://help.launchpad.net/ListHelp
>>
> 
> 
> 


-- 
Vadim Tkachenko, CTO
Percona Inc.
ICQ: 369-510-335, Skype: vadimtk153, Phone +1-888-401-3403
MySQL Performance Blog - http://www.mysqlperformanceblog.com
MySQL Consulting http://www.percona.com/

  Attend the 2009 Percona Performance Conference
  April 22-23 - http://conferences.percona.com/