Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753210Ab0BUUqh (ORCPT ); Sun, 21 Feb 2010 15:46:37 -0500 Received: from ogre.sisk.pl ([217.79.144.158]:58440 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752789Ab0BUUqf (ORCPT ); Sun, 21 Feb 2010 15:46:35 -0500 From: "Rafael J. Wysocki" To: Alan Jenkins Subject: Re: s2disk hang update Date: Sun, 21 Feb 2010 21:47:07 +0100 User-Agent: KMail/1.12.4 (Linux/2.6.33-rc8-rjw; KDE/4.3.5; x86_64; ; ) Cc: Mel Gorman , hugh.dickins@tiscali.co.uk, Pavel Machek , pm list , "linux-kernel" , Kernel Testers List References: <9b2b86521001020703v23152d0cy3ba2c08df88c0a79@mail.gmail.com> <201002182104.49631.rjw@sisk.pl> <9b2b86521002190348k61e3bce0m8d036d1068c05644@mail.gmail.com> In-Reply-To: <9b2b86521002190348k61e3bce0m8d036d1068c05644@mail.gmail.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201002212147.07987.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3642 Lines: 92 On Friday 19 February 2010, Alan Jenkins wrote: > On 2/18/10, Rafael J. Wysocki wrote: > > On Thursday 18 February 2010, Alan Jenkins wrote: > >> On 2/17/10, Rafael J. Wysocki wrote: > >> > On Wednesday 17 February 2010, Alan Jenkins wrote: > >> >> On 2/16/10, Rafael J. Wysocki wrote: > >> >> > On Tuesday 16 February 2010, Alan Jenkins wrote: > >> >> >> On 2/16/10, Alan Jenkins wrote: > >> >> >> > On 2/15/10, Rafael J. Wysocki wrote: > >> >> >> >> On Tuesday 09 February 2010, Alan Jenkins wrote: > >> >> >> >>> Perhaps I spoke too soon. I see the same hang if I run too many > >> >> >> >>> applications. The first hibernation fails with "not enough > >> >> >> >>> swap" > >> >> >> >>> as > >> >> >> >>> expected, but the second or third attempt hangs (with the same > >> >> >> >>> backtrace > >> >> >> >>> as before). > >> >> >> >>> > >> >> >> >>> The patch definitely helps though. Without the patch, I see a > >> >> >> >>> hang > >> >> >> >>> the > >> >> >> >>> first time I try to hibernate with too many applications > >> >> >> >>> running. > >> >> >> >> > >> >> >> >> Well, I have an idea. > >> >> >> >> > >> >> >> >> Can you try to apply the appended patch in addition and see if > >> >> >> >> that > >> >> >> >> helps? > >> >> >> >> > >> >> >> >> Rafael > >> >> >> > > >> >> >> > It doesn't seem to help. > >> >> >> > >> >> >> To be clear: It doesn't stop the hang when I hibernate with too many > >> >> >> applications. > >> >> >> > >> >> >> It does stop the same hang in a different case though. > >> >> >> > >> >> >> 1. boot with init=/bin/bash > >> >> >> 2. run s2disk > >> >> >> 3. cancel the s2disk > >> >> >> 4. repeat steps 2&3 > >> >> >> > >> >> >> With the patch, I can run 10s of iterations, with no hang. > >> >> >> Without the patch, it soon hangs, (in disable_nonboot_cpus(), as > >> >> >> always). > >> >> >> > >> >> >> That's what happens on 2.6.33-rc7. On 2.6.30, there is no problem. > >> >> >> On 2.6.31 and 2.6.32 I don't get a hang, but dmesg shows an > >> >> >> allocation > >> >> >> failure after a couple of iterations ("kthreadd: page allocation > >> >> >> failure. order:1, mode:0xd0"). It looks like it might be the same > >> >> >> stop_machine thread allocation failure that causes the hang. > >> >> > > >> >> > Have you tested it alone or on top of the previous one? If you've > >> >> > tested it > >> >> > alone, please apply the appended one in addition to it and retest. > >> >> > > >> >> > Rafael > >> >> > >> >> I did test with both patches applied together - > >> >> > >> >> 1. [Update] MM / PM: Force GFP_NOIO during suspend/hibernation and > >> >> resume > >> >> 2. "reducing the number of pages that we're going to keep preallocated > >> >> by > >> >> 20%" > >> > > >> > In that case you can try to reduce the number of preallocated pages even > >> > more, > >> > ie. change "/ 5" to "/ 2" (for example) in the second patch. > >> > >> It still hangs if I try to hibernate a couple of times with too many > >> applications. > > > > Hmm. I guess I asked that before, but is this a 32-bit or 64-bit system and > > how much RAM is there in the box? > > > > Rafael > > EeePC 701. 32 bit. 512Mb RAM. 350Mb swap file, on a "first-gen" SSD. Hmm. I'd try to make free_unnecessary_pages() free all of the preallocated pages and see what happens. 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/