Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756693AbZGEJzj (ORCPT ); Sun, 5 Jul 2009 05:55:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756699AbZGEJzZ (ORCPT ); Sun, 5 Jul 2009 05:55:25 -0400 Received: from rv-out-0506.google.com ([209.85.198.236]:9037 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756345AbZGEJzX (ORCPT ); Sun, 5 Jul 2009 05:55:23 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=gPGbPKPPMZf3l+O7DcHVT9bQocV9f2JVHESLdCtUTVqgn3KdsFZi6HYgVBD8gVsHG8 lFePb0ZTAqkritGLwqKlitFaqVxgzi9HkD3Xb+hsNIGNMz9yKWBUZgS5RntZAfOgDkfc NjXFUjveHajD6szL+KhMJsR01W2qOT6s1zpMs= Date: Sun, 5 Jul 2009 17:55:21 +0800 From: Wu Fengguang To: Rik van Riel Cc: KOSAKI Motohiro , David Woodhouse , David Howells , Minchan Kim , Mel Gorman , Johannes Weiner , Andrew Morton , LKML , Christoph Lameter , "peterz@infradead.org" , "tytso@mit.edu" , "linux-mm@kvack.org" , "elladan@eskimo.com" , "npiggin@suse.de" , "Barnes, Jesse" Subject: Re: Found the commit that causes the OOMs Message-ID: <20090705095520.GA31587@localhost> References: <20090701021645.GA6356@localhost> <20090701022644.GA7510@localhost> <20090701114959.85D3.A69D9226@jp.fujitsu.com> <4A4AD07E.2040508@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4A4AD07E.2040508@redhat.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1347 Lines: 38 On Tue, Jun 30, 2009 at 10:57:02PM -0400, Rik van Riel wrote: > KOSAKI Motohiro wrote: > >>> [ 1522.019259] Active_anon:11 active_file:6 inactive_anon:0 >>> [ 1522.019260] inactive_file:0 unevictable:0 dirty:0 writeback:0 unstable:0 >>> [ 1522.019261] free:1985 slab:44399 mapped:132 pagetables:61830 bounce:0 >>> [ 1522.019262] isolate:69817 >> >> OK. thanks. >> I plan to submit this patch after small more tests. it is useful for OOM analysis. > > It is also useful for throttling page reclaim. > > If more than half of the inactive pages in a zone are > isolated, we are probably beyond the point where adding > additional reclaim processes will do more harm than good. Maybe we can try limiting the isolation phase of direct reclaims to one per CPU? mutex_lock(per_cpu_lock); isolate_pages(); shrink_page_list(); put_back_pages(); mutex_unlock(per_cpu_lock); This way the isolated pages as well as major parts of direct reclaims will be bounded by CPU numbers. The added overheads should be trivial comparing to the reclaim costs. Thanks, Fengguang -- 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/