Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757980AbZCWO7e (ORCPT ); Mon, 23 Mar 2009 10:59:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752173AbZCWO7Z (ORCPT ); Mon, 23 Mar 2009 10:59:25 -0400 Received: from gir.skynet.ie ([193.1.99.77]:45486 "EHLO gir.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751283AbZCWO7Y (ORCPT ); Mon, 23 Mar 2009 10:59:24 -0400 Date: Mon, 23 Mar 2009 14:59:21 +0000 From: Mel Gorman To: Christoph Lameter Cc: Linux Memory Management List , KOSAKI Motohiro , Nick Piggin , Linux Kernel Mailing List , Lin Ming , Zhang Yanmin , Peter Zijlstra , Andrew Morton Subject: Re: [PATCH 00/25] Cleanup and optimise the page allocator V5 Message-ID: <20090323145921.GC15416@csn.ul.ie> References: <1237543392-11797-1-git-send-email-mel@csn.ul.ie> <20090320153723.GO24586@csn.ul.ie> <20090320162716.GP24586@csn.ul.ie> <20090323115213.GC6484@csn.ul.ie> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1102 Lines: 25 On Mon, Mar 23, 2009 at 09:30:26AM -0400, Christoph Lameter wrote: > On Mon, 23 Mar 2009, Mel Gorman wrote: > > > This came up again. There was some evidence when it was introduced that > > it worked and micro-benchmarks can show it to be of some use. It's > > not-obvious-enough that I'd be wary of deleting it. > > Certainly there is some minimal benefit. But maybe that benefit will > vanish if you drop the doubly linked list? > Extremely difficult to tell. It only makes a difference if you are not over a cache-line boundary using a singly linked list. If the structure is within a cache-line boundary with either single or double linked lists, it probably makes no measurable difference. -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/