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Date: Mon, 4 Aug 2008 21:25:29 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Nick Piggin <nickpiggin@yahoo.com.au>
cc: Andrew Morton <akpm@linux-foundation.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: Switching TestSetPageLocked to trylock_page
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On Tue, 5 Aug 2008, Nick Piggin wrote:
> 
> The part that helps x86 is another patch further down my stack, which
> can avoid looking at the hashed page waitqueue at unlock_page-time.
> Basically this eliminates the entire page waitqueue from the cache
> footprint of fastpath workloads where the lock is uncontended (often:
> page faulting, write(2), writeout etc).

Hmm. Tell me more. Contention bit?

		Linus