From owner-freebsd-current@FreeBSD.ORG Sat Sep 4 03:33:37 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2501816A4CE; Sat, 4 Sep 2004 03:33:37 +0000 (GMT) Received: from ganymede.hub.org (blk-222-46-91.eastlink.ca [24.222.46.91]) by mx1.FreeBSD.org (Postfix) with ESMTP id B474143D49; Sat, 4 Sep 2004 03:33:27 +0000 (GMT) (envelope-from scrappy@hub.org) Received: by ganymede.hub.org (Postfix, from userid 1000) id 432E9399D2; Sat, 4 Sep 2004 00:33:27 -0300 (ADT) Received: from localhost (localhost [127.0.0.1]) by ganymede.hub.org (Postfix) with ESMTP id 4254C399C4; Sat, 4 Sep 2004 00:33:27 -0300 (ADT) Date: Sat, 4 Sep 2004 00:33:27 -0300 (ADT) From: "Marc G. Fournier" To: Don Lewis In-Reply-To: <200409032158.i83LwdWg030214@gw.catspoiler.org> Message-ID: <20040904003222.J812@ganymede.hub.org> References: <200409032158.i83LwdWg030214@gw.catspoiler.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed cc: freebsd-current@freebsd.org Subject: Re: what is fsck's "slowdown"? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 04 Sep 2004 03:33:37 -0000 On Fri, 3 Sep 2004, Don Lewis wrote: > On 3 Sep, Marc G. Fournier wrote: >> >> I'm running another fsck on a 4.x system ... I know 5.x brings in the >> background mode for it, which would definitely make my life easier, *but* >> ... when running fsck, it says its using up 99% of the CPU: >> >> # ps aux | grep fsck >> root 67 99.0 5.0 184252 184284 p0 R+ 12:46PM 254:16.68 fsck -y /vm >> >> now, its a dual CPU system ... on an MP system, is it not possible to have >> it parallelize on a file system, so that it makes use of all available >> CPU? >> >> For instance, right now, its in Phase 4 ... on a file system where ctl-t >> shows: >> >> load: 0.99 cmd: fsck 67 [running] 15192.26u 142.30s 99% 184284k >> /dev/da0s1h: phase 4: cyl group 408 of 866 (47%) >> >> wouldn't it be possible, on a dual CPU system, to have group 434 and above >> run on one process, while group 433 and below running on the second, in >> parallel? Its not like the drives are being beat up: > > Would the file system in question happen to be full of UNREF files that > fsck is deleting? mostly 'ZERO LENGTH DIRECTORY' ... ---- Marc G. Fournier Hub.Org Networking Services (http://www.hub.org) Email: scrappy@hub.org Yahoo!: yscrappy ICQ: 7615664