percona-discussion team mailing list archive

[MARK CALLAGHAN <mdcallag@xxxxxxxxx>]

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?

>
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-- 
Mark Callaghan
mdcallag@xxxxxxxxx