From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030284AbXCMMSN (ORCPT ); Tue, 13 Mar 2007 08:18:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030297AbXCMMSN (ORCPT ); Tue, 13 Mar 2007 08:18:13 -0400 Received: from smtp107.mail.mud.yahoo.com ([209.191.85.217]:34538 "HELO smtp107.mail.mud.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1030284AbXCMMSN (ORCPT ); Tue, 13 Mar 2007 08:18:13 -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=Pjb2772skoaLOX+R2MqgUffdI1VDYmo1zvpDgPo70ngc1/LRjaPCp1/5ooq7r8wYMcFvQCpx7gRYQ2wbEBRoTebr4Qg+Q2vW1ssC5SaDUdxQrQp7CEgiF1LIu90XmnUmRp3X9u867iF24uIwtuFFRgBnay/Tc1zUXWHuYTBYaKA= ; X-YMail-OSG: vTq_WigVM1m32tzJPGSx772uvKWX36p.mesCM6u4A8BBfeJmMBt0wE5Qv_XJaC_DTPXFdAb6C8KzI2mPUaI.CfOPRoXkO_5M_QkYHl8T9tTfskBd1Mg0xJKxP7rUuXDUzIVIN1DeiJkgy9szhiRRPEJxsg-- Message-ID: <45F6967F.4020002@yahoo.com.au> Date: Tue, 13 Mar 2007 23:18:07 +1100 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: Andrew Morton CC: clameter@sgi.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [QUICKLIST 0/4] Arch independent quicklists V2 References: <20070313071325.4920.82870.sendpatchset@schroedinger.engr.sgi.com> <20070313005334.853559ca.akpm@linux-foundation.org> <45F65ADA.9010501@yahoo.com.au> <20070313035250.f908a50e.akpm@linux-foundation.org> <45F685C6.8070806@yahoo.com.au> <20070313041551.565891b5.akpm@linux-foundation.org> <45F68B4B.9020200@yahoo.com.au> <20070313044756.b45649ac.akpm@linux-foundation.org> <45F69287.8040509@yahoo.com.au> <20070313051109.3215104b.akpm@linux-foundation.org> In-Reply-To: <20070313051109.3215104b.akpm@linux-foundation.org> 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 Andrew Morton wrote: >>On Tue, 13 Mar 2007 23:01:11 +1100 Nick Piggin wrote: >>Andrew Morton wrote: >>>It would be interesting to look at a) leave the page full of random garbage >>>if we're releasing the whole mm and b) return it straight to the page allocator. >> >>Well we have the 'fullmm' case, which avoids all the locked pte operations >>(for those architectures where hardware pt walking requires atomicity). > > > I suspect there are some tlb operations which could be skipped in that case > too. Depends on the tlb flush implementation. The generic one doesn't look like it is all that smart about optimising the fullmm case. It does skip some tlb flushing though. >>However we still have to visit those to-be-unmapped parts of the page table >>to find the pages and free them. So we still at least need to bring it into >>cache for the read... at which point, the store probably isn't a big burden. > > > It means all that data has to be written back. Yes, I expect it'll prove > to be less costly than the initial load. Still, it is something we could try. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com