threads/136345: Recursive read rwlocks in thread A cause deadlock with write lock in thread B

[Attilio Rao]

2009/7/15 Nick Esborn <nick at desert.net>:
> The following reply was made to PR threads/136345; it has been noted by GNATS.
>
> From: Nick Esborn <nick at desert.net>
> To: bug-followup at FreeBSD.org,
>  rink at FreeBSD.org
> Cc:
> Subject: Re: threads/136345: Recursive read rwlocks in thread A cause deadlock with write lock in thread B
> Date: Wed, 15 Jul 2009 14:32:38 -0700
>
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>
>  Even after the above patch, I still run into occasional MySQL thread
>  deadlocks, which I originally described in what is now threads/135673.
>
>  I also posted on freebsd-current a few days ago:
>
>    http://lists.freebsd.org/pipermail/freebsd-current/2009-July/009328.html
>
>  I'd be happy to collect whatever data would be helpful in tracking
>  down this deadlock.  This only seems to happen under our production
>  workload, so that might make it harder to capture meaningful debug
>  data, but I'm certainly willing to try.  I can also arrange for
>  developer access to the system in question, if that would help
>  significantly.

So did you backport this to 7 and still experience deadlocks?
I just committed the fix to HEAD not to STABLE branch.

Thanks,
Attilio


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