Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759754AbYBTBE3 (ORCPT ); Tue, 19 Feb 2008 20:04:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755354AbYBTBEV (ORCPT ); Tue, 19 Feb 2008 20:04:21 -0500 Received: from relay1.sgi.com ([192.48.171.29]:39633 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755131AbYBTBEU (ORCPT ); Tue, 19 Feb 2008 20:04:20 -0500 Date: Wed, 20 Feb 2008 12:04:06 +1100 From: David Chinner To: Ferenc Wagner Cc: David Chinner , linux-kernel@vger.kernel.org Subject: Re: inode leak in 2.6.24? Message-ID: <20080220010405.GF155407@sgi.com> References: <87hcg9hkpp.fsf@szonett.ki.iif.hu> <20080218215344.GM155407@sgi.com> <87skzoanq3.fsf@szonett.ki.iif.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87skzoanq3.fsf@szonett.ki.iif.hu> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2716 Lines: 61 On Tue, Feb 19, 2008 at 05:57:08PM +0100, Ferenc Wagner wrote: > David Chinner writes: > > On Sat, Feb 16, 2008 at 12:18:58AM +0100, Ferenc Wagner wrote: > So, I loaded the same kernel on a different machine, but that seems to > exhibit a very similar behaviour. The machine is absolutely idle, > nobody logged in during this period, though an updatedb ran during > this period. However, the increase seems steady, not correlated to > cron.daily. > > The contents of /proc/sys/fs/inode-nr after reboot was: > 4421 95 > > and now, 13h35m later it's: > 146182 0 > > Find the two slabinfo outputs attached. Content-Description: slabinfo output immediately after reboot > xfs_inode 791 800 384 10 1 : tunables 54 27 8 : slabdata 80 80 0 > xfs_vnode 790 790 384 10 1 : tunables 54 27 8 : slabdata 79 79 0 > dentry 5133 5133 132 29 1 : tunables 120 60 8 : slabdata 177 177 0 Content-Description: slabinfo output 13h35m after reboot > xfs_inode 142548 142550 384 10 1 : tunables 54 27 8 : slabdata 14255 14255 0 > xfs_vnode 142548 142550 384 10 1 : tunables 54 27 8 : slabdata 14255 14255 0 > dentry 148003 148074 132 29 1 : tunables 120 60 8 : slabdata 5106 5106 0 > The xfs_inode, xfs_vnode and dentry lines show significant increase. > The machine indeed uses XFS as its root filesystem. Hope this gives > enough clues to narrow down the problem. I can try other kernels if > needed. The xfs inodes are clearly pinned by the dentry cache, so the issue is dentries, not inodes. What's causing dentries not to be reclaimed? I can't see anything that cold pin them (e.g. no filp's that would indicate open files being responsible), so my initial thoughts are that memory reclaim may have changed behaviour. I guess the first thing to find out is whether memory pressure results in freeing the dentries. To simulate memory pressure causing slab cache reclaim, can you run: # echo 2 > /proc/sys/vm/drop_caches and see if the number of dentries and inodes drops. If the number goes down significantly, then we aren't leaking dentries and there's been a change in memoy reclaim behaviour. If it stays the same, then we probably are leaking dentries.... Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group -- 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/