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Date: Fri, 14 Oct 2011 08:57:16 -0500 (CDT)
From: Christoph Lameter <cl@gentwo.org>
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To: Dimitri Sivanich <sivanich@sgi.com>
cc: Andrew Morton <akpm@linux-foundation.org>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, Mel Gorman <mel@csn.ul.ie>
Subject: Re: [PATCH] Reduce vm_stat cacheline contention in
 __vm_enough_memory
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On Fri, 14 Oct 2011, Dimitri Sivanich wrote:

> Testing on a smaller machine with 46 writer threads in parallel (my original
> test used 120).
>
> Looks as though cache-aligning and padding the end of the vm_stat array
> results in a ~150 MB/sec speedup.  This is a nice improvement for only 46
> writer threads, though it's not the full ~250 MB/sec speedup I get from
> setting OVERCOMMIT_NEVER.

Add to this the increase in the deltas for the ZVCs and change the stat
interval to 10 sec?