Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934287Ab1ETEUR (ORCPT ); Fri, 20 May 2011 00:20:17 -0400 Received: from mail-qy0-f174.google.com ([209.85.216.174]:41822 "EHLO mail-qy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751268Ab1ETEUQ convert rfc822-to-8bit (ORCPT ); Fri, 20 May 2011 00:20:16 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=DR9h81/Nr5alepy8U4pihvwtlnKNRHcFXCkAIEPe7WZMt9Gli/Z7iX5Uxgd18W0uBT GSpSWXiX04PFFtm1RlfD+kLGO8pnJLf5BffbdnEhJWbThdP2QnL5FIOB2MnFVX8oCd7m My3sR+1dlM2StqxAsP6qW+PEHqKuZgl3YxlLI= MIME-Version: 1.0 In-Reply-To: References: <20110512054631.GI6008@one.firstfloor.org> <20110514165346.GV6008@one.firstfloor.org> <20110514174333.GW6008@one.firstfloor.org> <20110515152747.GA25905@localhost> <20110517060001.GC24069@localhost> <4DD5DC06.6010204@jp.fujitsu.com> Date: Fri, 20 May 2011 13:20:15 +0900 Message-ID: Subject: Re: Kernel falls apart under light memory pressure (i.e. linking vmlinux) From: Minchan Kim To: Andrew Lutomirski Cc: KOSAKI Motohiro , kamezawa.hiroyu@jp.fujitsu.com, fengguang.wu@intel.com, andi@firstfloor.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, mgorman@suse.de, hannes@cmpxchg.org, riel@redhat.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2461 Lines: 71 On Fri, May 20, 2011 at 12:38 PM, Andrew Lutomirski wrote: > On Thu, May 19, 2011 at 11:12 PM, KOSAKI Motohiro > wrote: >>> Right after that happened, I hit ctrl-c to kill test_mempressure.sh. >>> The system was OK until I typed sync, and then everything hung. >>> >>> I'm really confused.  shrink_inactive_list in >>> RECLAIM_MODE_LUMPYRECLAIM will call one of the isolate_pages functions >>> with ISOLATE_BOTH.  The resulting list goes into shrink_page_list, >>> which does VM_BUG_ON(PageActive(page)). >>> >>> How is that supposed to work? >> >> Usually clear_active_flags() clear PG_active before calling >> shrink_page_list(). >> >> shrink_inactive_list() >>    isolate_pages_global() >>    update_isolated_counts() >>        clear_active_flags() >>    shrink_page_list() >> >> > > That makes sense.  And I have CONFIG_COMPACTION=y, so the lumpy mode > doesn't get set anyway. Could you see the problem with disabling CONFIG_COMPACTION? > > But the pages I'm seeing have flags=100000000008005D.  If I'm reading > it right, that means locked,referenced,uptodate,dirty,active.  How > does a page like that end up in shrink_page_list?  I don't see how a > page that's !PageLRU can get marked Active.  Nonetheless, I'm hitting > that VM_BUG_ON. Thanks for proving that it's not a problem of latest my patch. > > Is there a race somewhere? First of all, let's finish your first problem about hang. :) And let's make another thread to fix this problem. I think this is a severe problem because 2.6.39 includes my deactivate_pages (http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=315601809d124d046abd6c3ffa346d0dbd7aa29d) It touches page states more and more. (2.6.38.6 doesn't include it so it's not a problem of my deactivate_pages problem) And now inorder-putback series which I will push for 2.6.40 touches it more and more. So I want to resolve your problem asap. We don't have see report about that. Could you do git-bisect? FYI, Recently, big change of mm is compaction,transparent huge pages. Kame, could you point out thing related to memcg if you have a mind? > > --Andy > -- Kind regards, Minchan Kim -- 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/