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Date: Mon, 27 Jun 2005 00:46:24 -0700
From: Andrew Morton <akpm@osdl.org>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [rfc] lockless pagecache
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Nick Piggin <nickpiggin@yahoo.com.au> wrote:
>
> First I'll put up some numbers to get you interested - of a 64-way Altix
>  with 64 processes each read-faulting in their own 512MB part of a 32GB
>  file that is preloaded in pagecache (with the proper NUMA memory
>  allocation).

I bet you can get a 5x to 10x reduction in ->tree_lock traffic by doing
16-page faultahead.