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Date: Thu, 26 Sep 2002 06:17:40 -0700
From: William Lee Irwin III <wli@holomorphy.com>
To: Dipankar Sarma <dipankar@in.ibm.com>
Cc: Andrew Morton <akpm@digeo.com>, lkml <linux-kernel@vger.kernel.org>,
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Subject: Re: 2.5.38-mm3
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On Thu, Sep 26, 2002 at 05:42:44AM -0700, William Lee Irwin III wrote:
>> This is only aggravated by cacheline bouncing on SMP. The reductions
>> of system cpu time will doubtless be beneficial for all.

On Thu, Sep 26, 2002 at 06:35:58PM +0530, Dipankar Sarma wrote:
> On SMP, I would have thought that only sharing the fd table
> while cloning tasks (CLONE_FILES) affects performance by bouncing the rwlock
> cache line. Are there a lot of common workloads where this happens ?
> Anyway the files_struct_rcu patch for 2.5.38 is up at
> http://sourceforge.net/project/showfiles.php?group_id=8875&release_id=112473

It looks very unusual, but it is very real. Some of my prior profile
results show this. I'll run a before/after profile with this either
tonight or tomorrow night (it's 6:06AM PST here -- tonight is unlikely).


Cheers,
Bill
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