From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758089AbXGPIiV (ORCPT ); Mon, 16 Jul 2007 04:38:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754744AbXGPIiH (ORCPT ); Mon, 16 Jul 2007 04:38:07 -0400 Received: from smtp106.mail.mud.yahoo.com ([209.191.85.216]:47326 "HELO smtp106.mail.mud.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754634AbXGPIh4 (ORCPT ); Mon, 16 Jul 2007 04:37:56 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:X-YMail-OSG:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=AP03/GnLS0DrEU6mREN9LyRdNDskl2E6KbNp+FfI/Yanlfrpx8AzOyQAmBPZXI1ijhQO4J24DVsoH4sEcpFUgJM5nROfXsnb8M04ZROeSpLYa+6qggwMSxGgKou261uhMWr7meoM5Gdsz7tm1N6vZXtD5+HRQNXCFnKg438fA3E= ; X-YMail-OSG: 8wx8VTcVM1m4Xt2fnMhoVlvDeinWmlIAN34u87I0_Sx_HhIKglav0ZMo9tOV.eiNGYkPt8H0UQ-- Message-ID: <469B2E4D.6050404@yahoo.com.au> Date: Mon, 16 Jul 2007 18:37:33 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.12) Gecko/20051007 Debian/1.7.12-1 X-Accept-Language: en MIME-Version: 1.0 To: Pekka Enberg CC: Matt Mackall , linux-kernel , akpm@linux-foundation.org, Christoph Lameter Subject: Re: [PATCH] slob: reduce list scanning References: <20070714055434.GQ11115@waste.org> <469B09AB.5010309@yahoo.com.au> <84144f020707160022p37a2d712g21c3d5c89ed6345d@mail.gmail.com> In-Reply-To: <84144f020707160022p37a2d712g21c3d5c89ed6345d@mail.gmail.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Pekka Enberg wrote: > On 7/16/07, Nick Piggin wrote: > >> Actually SLOB potentially has some fundamental CPU cache hotness >> advantages over the other allocators, for the same reasons as >> its space advantages. > > > Because consecutive allocations hit the same cache-hot page regardless > of requested size where as SLUB by definition distributes allocations > to different pages (some of which may not be hot)? Yeah, that, and also a newly freed slab object is quite likely to be hot, and that memory can be used by another subsequent allocation -- not always, because the allocation heuristics may not place it there, but there is potential that is impossible with slab allocators. -- SUSE Labs, Novell Inc.