From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752821Ab1JVGVv (ORCPT ); Sat, 22 Oct 2011 02:21:51 -0400 Received: from mail-iy0-f174.google.com ([209.85.210.174]:63579 "EHLO mail-iy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751250Ab1JVGVu convert rfc822-to-8bit (ORCPT ); Sat, 22 Oct 2011 02:21:50 -0400 From: Nai Xia Reply-To: nai.xia@gmail.com To: =?utf-8?q?Pawe=C5=82_Sikora?= Subject: Re: kernel 3.0: BUG: soft lockup: find_get_pages+0x51/0x110 Date: Sat, 22 Oct 2011 14:21:23 +0800 User-Agent: KMail/1.13.6 (Linux/2.6.38-8-generic-pae; KDE/4.6.5; i686; ; ) Cc: Hugh Dickins , arekm@pld-linux.org, Linus Torvalds , linux-mm@kvack.org, Mel Gorman , jpiszcz@lucidpixels.com, linux-kernel@vger.kernel.org, Andrew Morton , Andrea Arcangeli References: <201110122012.33767.pluto@agmk.net> <201110212336.47267.pluto@agmk.net> In-Reply-To: <201110212336.47267.pluto@agmk.net> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 8BIT Message-Id: <201110221421.23181.nai.xia@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Saturday 22 October 2011 05:36:46 Paweł Sikora wrote: > On Friday 21 of October 2011 11:07:56 Nai Xia wrote: > > On Fri, Oct 21, 2011 at 4:07 PM, Pawel Sikora wrote: > > > On Friday 21 of October 2011 14:22:37 Nai Xia wrote: > > > > > >> And as a side note. Since I notice that Pawel's workload may include OOM, > > > > > > my last tests on patched (3.0.4 + migrate.c fix + vserver) kernel produce full cpu load > > > on dual 8-cores opterons like on this htop screenshot -> http://pluto.agmk.net/kernel/screen1.png > > > afaics all userspace applications usualy don't use more than half of physical memory > > > and so called "cache" on htop bar doesn't reach the 100%. > > > > OK，did you logged any OOM killing if there was some memory usage burst? > > But, well my above OOM reasoning is a direct short cut to imagined > > root cause of "adjacent VMAs which > > should have been merged but in fact not merged" case. > > Maybe there are other cases that can lead to this or maybe it's > > totally another bug.... > > i don't see any OOM killing with my conservative settings > (vm.overcommit_memory=2, vm.overcommit_ratio=100). OK, that does not matter now. Andrea showed us a simpler way to goto this bug. > > > But still I think if my reasoning is good, similar bad things will > > happen again some time in the future, > > even if it was not your case here... > > > > > > > > the patched kernel with disabled CONFIG_TRANSPARENT_HUGEPAGE (new thing in 2.6.38) > > > died at night, so now i'm going to disable also CONFIG_COMPACTION/MIGRATION in next > > > steps and stress this machine again... > > > > OK, it's smart to narrow down the range first.... > > disabling hugepage/compacting didn't help but disabling hugepage/compacting/migration keeps > opterons stable for ~9h so far. userspace uses ~40GB (from 64) ram, caches reach 100% on htop bar, > average load ~16. i wonder if it survive weekend... > Maybe you should give another shot of Andrea's latest anon_vma_order_tail() patch. :)