Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964958AbWILHkK (ORCPT ); Tue, 12 Sep 2006 03:40:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964959AbWILHkK (ORCPT ); Tue, 12 Sep 2006 03:40:10 -0400 Received: from mail.dsa-ac.de ([62.112.80.99]:779 "EHLO mail.dsa-ac.de") by vger.kernel.org with ESMTP id S964958AbWILHkI (ORCPT ); Tue, 12 Sep 2006 03:40:08 -0400 Date: Tue, 12 Sep 2006 09:40:03 +0200 (CEST) From: Guennadi Liakhovetski To: Nick Piggin Cc: linux-kernel@vger.kernel.org Subject: Re: [2.6.17.4] slabinfo.buffer_head increases In-Reply-To: <45061FCB.1000402@yahoo.com.au> Message-ID: References: <45061FCB.1000402@yahoo.com.au> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1749 Lines: 45 On Tue, 12 Sep 2006, Nick Piggin wrote: > Guennadi Liakhovetski wrote: > >>> On Mon, 10 Jul 2006, Guennadi Liakhovetski wrote: >>> >>>> I am obsering a steadily increasing buffer_head value in slabinfo under >>>> 2.6.17.4. I searched the net / archives and didn't find anything >>>> directly relevant. Does anyone have an idea or how shall we debug it? >>> >> >> The problem is still there under 2.6.18-rc2. I narrowed it down to ext3 >> journal. To reproduce one just has to mount an ext3 partition and perform >> (write) accesses to it. A loop { touch /mnt/foo; sleep 1; } suffices - just >> let it run for a couple of minutes and monitor buffer_head in >> /proc/slabinfo. If you mount it as ext2 the problem is gone. > > > What data mode is ext3 mounted with? Default, i.e., ordered, I guess. > Is the memory reclaimable? If yes, is it a problem? Yes, that's why I later wrote that the problem is not real. It was hard to see as we had a lot of free RAM on the system, the system was idle apart from one script that only did "touch x" periodically with the same "x" and the buffer_head slab was growing very steadily. Unlike with ext2 / reiserfs. That's why I decided it was not ok. But the memory is reclaimable, so, seems like not a problem. Just a bit odd that such a "harmless" operation causes a steady growth of buffer_heads... Thanks Guennadi --------------------------------- Guennadi Liakhovetski, Ph.D. DSA Daten- und Systemtechnik GmbH Pascalstr. 28 D-52076 Aachen Germany - 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/