Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750892AbVLGLae (ORCPT ); Wed, 7 Dec 2005 06:30:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750894AbVLGLae (ORCPT ); Wed, 7 Dec 2005 06:30:34 -0500 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:12233 "EHLO amd.ucw.cz") by vger.kernel.org with ESMTP id S1750890AbVLGLae (ORCPT ); Wed, 7 Dec 2005 06:30:34 -0500 Date: Wed, 7 Dec 2005 12:30:03 +0100 From: Pavel Machek To: "Rafael J. Wysocki" Cc: Andy Isaacson , Nigel Cunningham , Linux Kernel Mailing List Subject: Re: swsusp performance problems in 2.6.15-rc3-mm1 Message-ID: <20051207113003.GD2563@elf.ucw.cz> References: <20051205081935.GI22168@hexapodia.org> <200512070205.37414.rjw@sisk.pl> <20051207011019.GA2233@elf.ucw.cz> <200512071217.41814.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200512071217.41814.rjw@sisk.pl> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1519 Lines: 42 Hi! > > > > I'm suggesting that rather than writing the clean pages out to the > > > > image, simply make their metadata available to a post-resume userland > > > > helper. Something like > > > > > > > > % head -2 /dev/swsusp-helper > > > > /bin/sh 105-115 192 199-259 > > > > /lib/libc-2.3.2.so 1-250 > > > > > > > > where the userland program is expected to use the list of page numbers > > > > (and getpagesize(2)) to asynchronously page in the working set in an > > > > ionice'd manner. > > > > > > The helper is not necessary, I think. > > > > Actually, I like the helper. It is safest solution, > > No, it's not. > > Let me explain what I have in mind. > > For starters, please observe that the addresses we use are page-aligned, > so the least significant bit is always zero. Thus it can be used as a marker. > > Now before we save the image we can mark blank pages by setting > the least significant bit of .orig_address to 1 in the coresponding PBEs. > We save the "marked" .orig_address values to the image. Well, nice optimalization, but how many pages are actually full of zeros? Above has advantage of working with any "clean" pages -- like text pages of /bin/bash etc. And if done right it will not be intrusive... Pavel -- Thanks, Sharp! - 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/