From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755005Ab0JSCfk (ORCPT ); Mon, 18 Oct 2010 22:35:40 -0400 Received: from mga01.intel.com ([192.55.52.88]:25884 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753430Ab0JSCfj (ORCPT ); Mon, 18 Oct 2010 22:35:39 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.57,348,1283756400"; d="scan'208";a="618041627" Date: Tue, 19 Oct 2010 10:35:37 +0800 From: Wu Fengguang To: Minchan Kim Cc: KOSAKI Motohiro , Andrew Morton , Neil Brown , Rik van Riel , KAMEZAWA Hiroyuki , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "Li, Shaohua" Subject: Re: Deadlock possibly caused by too_many_isolated. Message-ID: <20101019023537.GB8310@localhost> References: <20101019093142.509d6947@notabene> <20101018154137.90f5325f.akpm@linux-foundation.org> <20101019095144.A1B0.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > @@ -2054,10 +2069,11 @@ rebalance: > goto got_pg; > > /* > - * If we failed to make any progress reclaiming, then we are > - * running out of options and have to consider going OOM > + * If we failed to make any progress reclaiming and there aren't > + * many parallel reclaiming, then we are unning out of options and > + * have to consider going OOM > */ > - if (!did_some_progress) { > + if (!did_some_progress && !too_many_isolated_zone(preferred_zone)) { > if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) { > if (oom_killer_disabled) > goto nopage; This is simply wrong. It disabled this block for 99% system because there won't be enough tasks to make (!too_many_isolated_zone == true). As a result the LRU will be scanned like mad and no task get OOMed when it should be. Thanks, Fengguang From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id 6E8EE6B00CE for ; Mon, 18 Oct 2010 22:35:40 -0400 (EDT) Date: Tue, 19 Oct 2010 10:35:37 +0800 From: Wu Fengguang Subject: Re: Deadlock possibly caused by too_many_isolated. Message-ID: <20101019023537.GB8310@localhost> References: <20101019093142.509d6947@notabene> <20101018154137.90f5325f.akpm@linux-foundation.org> <20101019095144.A1B0.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org To: Minchan Kim Cc: KOSAKI Motohiro , Andrew Morton , Neil Brown , Rik van Riel , KAMEZAWA Hiroyuki , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "Li, Shaohua" List-ID: > @@ -2054,10 +2069,11 @@ rebalance: > goto got_pg; > > /* > - * If we failed to make any progress reclaiming, then we are > - * running out of options and have to consider going OOM > + * If we failed to make any progress reclaiming and there aren't > + * many parallel reclaiming, then we are unning out of options and > + * have to consider going OOM > */ > - if (!did_some_progress) { > + if (!did_some_progress && !too_many_isolated_zone(preferred_zone)) { > if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) { > if (oom_killer_disabled) > goto nopage; This is simply wrong. It disabled this block for 99% system because there won't be enough tasks to make (!too_many_isolated_zone == true). As a result the LRU will be scanned like mad and no task get OOMed when it should be. Thanks, Fengguang -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org