Date: Thu, 21 Jan 2010 18:59:14 +0100
From: Andi Kleen <andi@firstfloor.org>
To: Don Mullis <don.mullis@gmail.com>
Cc: linux-kernel@vger.kernel.org, airlied@redhat.com, andi@firstfloor.org,
       david@fromorbit.com, dedekind@infradead.org
Subject: Re: [PATCH 1/2] lib: more scalable list_sort()
Message-ID: <20100121175914.GA8910@basil.fritz.box>
References: <87fx609i29.fsf@gmail.com>
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On Wed, Jan 20, 2010 at 08:51:26PM -0800, Don Mullis wrote:
> The use of list_sort() by UBIFS looks like it could generate long
> lists; this alternative implementation scales better, reaching ~3x
> performance gain as list length approaches the L2 cache size.

If this can really be called with long lists 
the function likely needs (optional) need_resched()s
Otherwise it could ruin scheduling latencies.

-Andi
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