Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262694AbVAFBdY (ORCPT ); Wed, 5 Jan 2005 20:33:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262695AbVAFBdY (ORCPT ); Wed, 5 Jan 2005 20:33:24 -0500 Received: from smtp203.mail.sc5.yahoo.com ([216.136.129.93]:61810 "HELO smtp203.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S262694AbVAFBdW (ORCPT ); Wed, 5 Jan 2005 20:33:22 -0500 Message-ID: <41DC955D.9020505@yahoo.com.au> Date: Thu, 06 Jan 2005 12:33:17 +1100 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.3) Gecko/20041007 Debian/1.7.3-5 X-Accept-Language: en MIME-Version: 1.0 To: Rik van Riel CC: Marcelo Tosatti , Andrew Morton , andrea@suse.de, linux-kernel@vger.kernel.org Subject: Re: [PATCH][5/?] count writeback pages in nr_scanned References: <20050105020859.3192a298.akpm@osdl.org> <20050105180651.GD4597@dualathlon.random> <20050105174934.GC15739@logos.cnet> <20050105134457.03aca488.akpm@osdl.org> <20050105203217.GB17265@logos.cnet> <41DC7D86.8050609@yahoo.com.au> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 913 Lines: 24 Rik van Riel wrote: > On Thu, 6 Jan 2005, Nick Piggin wrote: > >> I think what Andrea is worried about is that blk_congestion_wait is >> fairly vague, and can be a source of instability in the scanning >> implementation. > > > The recent OOM kill problem has been happening: > 1) with cache pressure on lowmem only, due to a block device write > 2) with no block congestion at all > 3) with pretty much all pageable lowmme pages in writeback state > > It appears the VM has trouble dealing with the situation where > there is no block congestion to wait on... > Try, together with your nr_scanned patch, to replace blk_congestion_wait with io_schedule_timeout. - 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/