Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932703AbWBUUkd (ORCPT ); Tue, 21 Feb 2006 15:40:33 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932714AbWBUUkd (ORCPT ); Tue, 21 Feb 2006 15:40:33 -0500 Received: from ogre.sisk.pl ([217.79.144.158]:25992 "EHLO ogre.sisk.pl") by vger.kernel.org with ESMTP id S932703AbWBUUkc (ORCPT ); Tue, 21 Feb 2006 15:40:32 -0500 From: "Rafael J. Wysocki" To: Dmitry Torokhov Subject: Re: Which is simpler? (Was Re: [Suspend2-devel] Re: [ 00/10] [Suspend2] Modules support.) Date: Tue, 21 Feb 2006 21:40:56 +0100 User-Agent: KMail/1.9.1 Cc: Nigel Cunningham , Andreas Happe , linux-kernel@vger.kernel.org, Suspend2 Devel List References: <20060201113710.6320.68289.stgit@localhost.localdomain> <200602211257.29161.ncunningham@cyclades.com> <200602202319.15018.dtor_core@ameritech.net> In-Reply-To: <200602202319.15018.dtor_core@ameritech.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200602212140.57566.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1227 Lines: 24 On Tuesday 21 February 2006 05:19, Dmitry Torokhov wrote: > On Monday 20 February 2006 21:57, Nigel Cunningham wrote: > > For the record, my thinking went: swsusp uses n (12?) bytes of meta data for > > every page you save, where as using bitmaps makes that much closer to a > > constant value (a small variable amount for recording where the image will be > > stored in extents). 12 bytes per page is 3MB/1GB. If swsusp was to add > > support for multiple swap partitions or writing to files, those requirements > > might be closer to 5MB/GB. > > 5MB/GB amounts to 0.5% overhead, I don't think you should be concerned here. > Much more important IMHO is that IIRC swsusp requires to be able to free 1/2 > of the physical memory whuch is hard on low memory boxes. I see another point in using bitmaps: we could avoid modifying page flags and use bitmaps to store all of the temporary information. I thought about it for some time and I think it's doable. Greetings, Rafael - 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/