Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754774Ab1DNXji (ORCPT ); Thu, 14 Apr 2011 19:39:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:33008 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753964Ab1DNXjg (ORCPT ); Thu, 14 Apr 2011 19:39:36 -0400 Date: Fri, 15 Apr 2011 01:38:42 +0200 From: Andrea Arcangeli To: Mel Gorman Cc: raz ben yehuda , lkml , riel@redhat.com, kosaki.motohiro@jp.fujitsu.com, akpm@linux-foundation.org Subject: Re: 2.6.38 page_test regression Message-ID: <20110414233842.GJ15707@random.random> References: <1302692638.15225.14.camel@raz.scalemp.com> <20110413125146.GR29444@random.random> <1302703579.17536.1.camel@raz.scalemp.com> <20110413172127.GB5734@random.random> <1302781754.5098.13.camel@raz.scalemp.com> <20110414150925.GD15707@random.random> <1302811643.10051.8.camel@raz.scalemp.com> <20110414215327.GI11871@csn.ul.ie> <20110414231648.GA30898@csn.ul.ie> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110414231648.GA30898@csn.ul.ie> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 560 Lines: 11 On Fri, Apr 15, 2011 at 12:16:48AM +0100, Mel Gorman wrote: > Theories better than slightly-different-register-use are welcome. __pte_alloc_one is now skipped 511 times every 512 page faults, so we call alloc_pages 512 times less and we take page_table_lock 512 times less, that explains it I think. We need it... -- 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/