From: Quentin Godfroy Subject: Re: possible (ext4 related?) memory leak in kernel 2.6.26 Date: Thu, 9 Oct 2008 01:52:46 +0200 Message-ID: <200810082355.m98NtZkQ012577@goelette.ens.fr> References: <20081003003548.GA18138@mit.edu> <20081005091526.GA678@goelette.ens.fr> <20081005122752.GB27335@mit.edu> <20081005161214.GA2985@goelette.ens.fr> <20081006025006.GA9289@mit.edu> <48EA2F20.7020309@redhat.com> <20081006175502.GA12937@mit.edu> <20081007221256.GF15929@mit.edu> <20081008000227.GA32052@goelette.ens.fr> <20081008005338.GH15929@mit.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: Theodore Tso , Eric Sandeen , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: Received: from nef2.ens.fr ([129.199.96.40]:2161 "EHLO nef2.ens.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754839AbYJHXz6 (ORCPT ); Wed, 8 Oct 2008 19:55:58 -0400 Content-Disposition: inline In-Reply-To: <20081008005338.GH15929@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Tue, Oct 07, 2008 at 08:53:38PM -0400, Theodore Tso wrote: > On Wed, Oct 08, 2008 at 02:02:27AM +0200, Quentin Godfroy wrote: > > > > I rebooted, but as I didn't know exactly how to trigger the bug except than > > by waiting a few days I was waiting to see. > > > > Do you have an idea about how to trigger the bug? > > The bug is that each time a transaction commits, if the buffer head > hasn't been leaked already, it will leak pinning the memory until the > total size of the journal is taking up memory. If you have a 2gigs of > memory, and a single filesystem with 256meg journal, you might not > notice the problem at all. If you less than 256 megs of memory, > you'll notice fairly quickly. Indeed after a couple of days of uptime the number of dirty blocks do not go further than ~50, so I think the bug is corrected as far as I am concerned. By the way, why does the kernel not commit to memory these remaining buffers when the memory is scarse (say instead of firing an OOM killer)? Regards Quentin Godfroy