From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: [RFD] swsusp problem: Drivers allocate much memory during suspend (was: Re: 2.6.21-rc5: swsusp: Not enough free memory) Date: Sat, 14 Apr 2007 00:10:16 +0200 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="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline In-Reply-To: <200704132241.52725.rjw@sisk.pl> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: "Rafael J. Wysocki" Cc: nigel@nigel.suspend2.net, linux-pm@lists.osdl.org, Jiri Slaby , Linux kernel mailing list List-Id: linux-pm@vger.kernel.org Hi! > > > Well, it looks like someone allocated about 6000 pages after we had f= reed > > > 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 r= eserve > 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 t= he > 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 m= emory > for suspending allocate it _before_ the memory shrinker is called. For t= his > purpose we can use notifiers that will be called before we start the shri= nking > 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/blo= g.html