Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932205AbVIJF2U (ORCPT ); Sat, 10 Sep 2005 01:28:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932612AbVIJF2U (ORCPT ); Sat, 10 Sep 2005 01:28:20 -0400 Received: from ppp59-167.lns1.cbr1.internode.on.net ([59.167.59.167]:51461 "EHLO triton.bird.org") by vger.kernel.org with ESMTP id S932205AbVIJF2T (ORCPT ); Sat, 10 Sep 2005 01:28:19 -0400 Message-ID: <43226FDA.4070607@acquerra.com.au> Date: Sat, 10 Sep 2005 15:32:10 +1000 From: Anthony Wesley Reply-To: awesley@acquerra.com.au User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.7.8) Gecko/20050511 X-Accept-Language: en-us, en MIME-Version: 1.0 To: nate.diller@gmail.com CC: linux-kernel@vger.kernel.org Subject: Re: kernel 2.6.13 buffer strangeness References: <432151B0.7030603@acquerra.com.au> <5c49b0ed05090914394dba42bf@mail.gmail.com> <432225E0.9030606@acquerra.com.au> <5c49b0ed0509091735436260bb@mail.gmail.com> <432231B7.2060200@acquerra.com.au> <5c49b0ed0509091847135834c0@mail.gmail.com> <432243AA.4000508@acquerra.com.au> <5c49b0ed05090922021b8f8112@mail.gmail.com> In-Reply-To: <5c49b0ed05090922021b8f8112@mail.gmail.com> 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: 1574 Lines: 40 Nate Diller wrote: > just found the culprit. guess i should have read the code the first > time. get_dirty_limits() in drivers/block/page_writeback.c has a > hard-coded upper limit to dirty_ratio. it's capped to half of the > unmapped pages, so maybe 30-40% of your system's memory. so if you are > brave, just remove the "/ 2" parts from the 'if (dirty_ratio > > unmapped_ratio / 2) dirty_ratio = unmapped_ratio / 2;' check, and you > can have all the OOM goodness you want. Excellent. OOM here I come. > i really recommend you focus on getting better disk bandwidth, you stand > to gain a lot more from that approach. i presume you're on ext3; > perhaps you should try reiser4 or xfs, they are more likely to meet your > disk bandwidth requirements. Yep, pursuing this as well, also looking to add more RAM to the machine. At this stage I was just trying to understand the numbers that I was seeing, so I could work out the best way to proceed. I'm using ext2 at the moment, on the assumption that the journal would cost me a bit of performance so I left it out :-) I'll certainly try the other filesystems as you suggest. Thanks again, Anthony -- Anthony Wesley Director and IT/Network Consultant Smart Networks Pty Ltd Acquerra Pty Ltd Anthony.Wesley@acquerra.com.au Phone: (02) 62595404 or 0419409836 - 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/