From owner-freebsd-hackers@FreeBSD.ORG Tue Jun 7 20:16:54 2005 Return-Path: X-Original-To: hackers@FreeBSD.org Delivered-To: freebsd-hackers@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 13C9216A41C; Tue, 7 Jun 2005 20:16:54 +0000 (GMT) (envelope-from dwmalone@maths.tcd.ie) Received: from salmon.maths.tcd.ie (salmon.maths.tcd.ie [134.226.81.11]) by mx1.FreeBSD.org (Postfix) with SMTP id D644543D53; Tue, 7 Jun 2005 20:16:52 +0000 (GMT) (envelope-from dwmalone@maths.tcd.ie) Received: from walton.maths.tcd.ie ([134.226.81.10] helo=walton.maths.tcd.ie) by salmon.maths.tcd.ie with SMTP id ; 7 Jun 2005 21:16:43 +0100 (BST) Date: Tue, 7 Jun 2005 21:16:42 +0100 From: David Malone To: Pawel Jakub Dawidek Message-ID: <20050607201642.GA58346@walton.maths.tcd.ie> References: <42A475AB.6020808@fer.hr> <20050607194005.GG837@darkness.comp.waw.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050607194005.GG837@darkness.comp.waw.pl> User-Agent: Mutt/1.5.6i Sender: dwmalone@maths.tcd.ie Cc: hackers@FreeBSD.org, scottl@FreeBSD.org, phk@FreeBSD.org, Ivan Voras Subject: Re: Google SoC idea X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 07 Jun 2005 20:16:54 -0000 On Tue, Jun 07, 2005 at 09:40:05PM +0200, Pawel Jakub Dawidek wrote: > +> Does it make sense to do it this way? Is it worth applying for the SoC? > > Not sure. Basically this is simlar what softupdate does, I think. > From another point of view softupdates are only available for UFS. > You probably wants to hear scottl and phk opinions (CCed). I think that Ivan's idea is kind of different from softupdates. His idea is pretty clever, in that it could provide synchronus random writes at sequential write speeds for any filesystem, providing you repaly the journal at startup. However, our main problem these days is the fact that we do an fsck after every unclean reboot, not the speed of writes. I guess that you could skip the fsck (or run it very slowly in the background) if you knew the filesystem was clean 'cos of jounral replay. David.