Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932361AbVLARoL (ORCPT ); Thu, 1 Dec 2005 12:44:11 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932365AbVLARoL (ORCPT ); Thu, 1 Dec 2005 12:44:11 -0500 Received: from cantor.suse.de ([195.135.220.2]:7055 "EHLO mx1.suse.de") by vger.kernel.org with ESMTP id S932361AbVLARoK (ORCPT ); Thu, 1 Dec 2005 12:44:10 -0500 From: Andreas Schwab To: Hugh Dickins Cc: Christopher Friesen , linux-kernel@vger.kernel.org Subject: Re: discrepency between "df" and "du" on tmpfs filesystem? References: <438F179E.5040402@nortel.com> X-Yow: The fact that 47 PEOPLE are yelling and sweat is cascading down my SPINAL COLUMN is fairly enjoyable!! Date: Thu, 01 Dec 2005 18:44:00 +0100 In-Reply-To: (Hugh Dickins's message of "Thu, 1 Dec 2005 16:41:15 +0000 (GMT)") Message-ID: User-Agent: Gnus/5.110003 (No Gnus v0.3) Emacs/22.0.50 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1367 Lines: 37 Hugh Dickins writes: > On Thu, 1 Dec 2005, Christopher Friesen wrote: >> >> Someone noticed this on one of our machines. The rootfs is a 256MB tmpfs >> filesystem. Depending on how you check the size, you get two different >> answers. >> >> root@10.41.50.66:/root> df -kl >> rootfs 262144 255684 6460 98% / >> >> root@10.41.50.66:/root> du -sxk / >> 204672 / >> >> Anyone know what's going on? > > df tells you what the filesystem says is in use or free, via statfs. > du goes looking at the contents of the filesystem, totalling stats. > Any files unlinked but held open will be counted by df but not by du. > There might also be a discrepancy over indirect blocks, I'm not sure. Also an empty filesystem usually does not have zero use, since the filesystem overhead (inode table, etc) may be accounted in the statfs counts. Andreas. -- Andreas Schwab, SuSE Labs, schwab@suse.de SuSE Linux Products GmbH, Maxfeldstra?e 5, 90409 N?rnberg, Germany PGP key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 "And now for something completely different." - 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/