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Date: Thu, 26 Apr 2012 10:45:28 +0800
From: David Xu <listlog2011@gmail.com>
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Cc: davidxu@FreeBSD.org, freebsd-threads@FreeBSD.org
Subject: Re: threads/167308: Performance regression in thread locking on
 8-stable [regression]
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On 2012/4/26 9:44, linimon@FreeBSD.org wrote:
> Old Synopsis: Perf regression in thread locking on 8-stable
> New Synopsis: Performance regression in thread locking on 8-stable [regression]
>
> Responsible-Changed-From-To: freebsd-threads->davidxu
> Responsible-Changed-By: linimon
> Responsible-Changed-When: Thu Apr 26 01:41:20 UTC 2012
> Responsible-Changed-Why:
> Over to committer of r234373.
>
> http://www.freebsd.org/cgi/query-pr.cgi?pr=167308
>
This is a known problem that the unlocking is not optimized when the mutex
is heavily contented, I may MFC wake2 later.