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

[Nick Esborn]

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.
 
 -nick
 
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 nick at desert.net - all messages cryptographically signed
 
 
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