From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754148AbXDMWKZ (ORCPT ); Fri, 13 Apr 2007 18:10:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754150AbXDMWKZ (ORCPT ); Fri, 13 Apr 2007 18:10:25 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:35320 "EHLO amd.ucw.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754148AbXDMWKY (ORCPT ); Fri, 13 Apr 2007 18:10:24 -0400 Date: Sat, 14 Apr 2007 00:10:16 +0200 From: Pavel Machek To: "Rafael J. Wysocki" Cc: nigel@nigel.suspend2.net, Jiri Slaby , Linux kernel mailing list , linux-pm@lists.osdl.org Subject: Re: [RFD] swsusp problem: Drivers allocate much memory during suspend (was: Re: 2.6.21-rc5: swsusp: Not enough free memory) Message-ID: <20070413221016.GQ28264@elf.ucw.cz> References: <460B6E4B.3060004@gmail.com> <200704131400.12021.rjw@sisk.pl> <1176466896.7112.159.camel@nigel.suspend2.net> <200704132241.52725.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200704132241.52725.rjw@sisk.pl> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.11+cvs20060126 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi! > > > Well, it looks like someone allocated about 6000 pages after we had freed > > > enough memory for suspending. > > > > We have a tunable allowance in Suspend2 for this, because fglrx > > allocates a lot of pages in its suspend routine if DRI is enabled. I > > think some other drivers do too, but fglrx is the main one I know. > > I wasn't aware of that, thanks for the information. > > I think this means we'll probably need to add a tunable, similar to image_size, > that will allow the users to specify how much spare memory they want to reserve > for suspending (instead of the constant PAGES_FOR_IO). IMO we can call it > 'spare_memory'. Just increase PAGES_FOR_IO. This should not be tunable. > Still, this doesn't look like a real solution, because it would require the > users affected by this problem to experiment with suspending in order to > figure out how much spare memory they will need. Exactly. > IMO to really fix the problem, we should let the drivers that need much memory > for suspending allocate it _before_ the memory shrinker is called. For this > purpose we can use notifiers that will be called before we start the shrinking > of memory. Namely, if a driver needs to allocate substantial amount > of memory Yes please. Using that notifier without leaking the memory will be "interesting" but if someone needs so much memory during suspend, let them eat their own complexity. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html