From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932080AbWFMMPm (ORCPT ); Tue, 13 Jun 2006 08:15:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932081AbWFMMPm (ORCPT ); Tue, 13 Jun 2006 08:15:42 -0400 Received: from [213.46.243.16] ([213.46.243.16]:26964 "EHLO amsfep17-int.chello.nl") by vger.kernel.org with ESMTP id S932080AbWFMMPl (ORCPT ); Tue, 13 Jun 2006 08:15:41 -0400 Subject: Re: [PATCH 1/6] mm: tracking shared dirty pages From: Peter Zijlstra To: Andi Kleen Cc: Hugh Dickins , Andrew Morton , David Howells , Christoph Lameter , Martin Bligh , Nick Piggin , Linus Torvalds , linux-kernel@vger.kernel.org In-Reply-To: References: <20060613112120.27913.71986.sendpatchset@lappy> <20060613112131.27913.43169.sendpatchset@lappy> Content-Type: text/plain Date: Tue, 13 Jun 2006 14:15:14 +0200 Message-Id: <1150200914.20886.135.camel@lappy> Mime-Version: 1.0 X-Mailer: Evolution 2.6.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2006-06-13 at 14:03 +0200, Andi Kleen wrote: > Peter Zijlstra writes: > > > From: Peter Zijlstra > > > > People expressed the need to track dirty pages in shared mappings. > > Why only shared mappings? Anonymous pages can be dirty too > and would need to be written to swap then before making progress. Anonymous pages are per definition dirty, as they don't have a persistent backing store. Each eviction of an anonymous page requires IO to swap space. On swap-in pages are removed from the swap space to make place for other pages. Peter