From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Thu, 24 Jul 2008 00:14:24 -0700 (PDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.168.28]) by oss.sgi.com (8.12.11.20060308/8.12.11/SuSE Linux 0.7) with ESMTP id m6O7EHF8021075 for ; Thu, 24 Jul 2008 00:14:18 -0700 Received: from ipmail01.adl6.internode.on.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 49031E93189 for ; Thu, 24 Jul 2008 00:15:27 -0700 (PDT) Received: from ipmail01.adl6.internode.on.net (ipmail01.adl6.internode.on.net [203.16.214.146]) by cuda.sgi.com with ESMTP id 327dAbE2TibWLc6H for ; Thu, 24 Jul 2008 00:15:27 -0700 (PDT) Date: Thu, 24 Jul 2008 17:15:19 +1000 From: Dave Chinner Subject: Re: [PATCH 4/4] fix biosize option Message-ID: <20080724071519.GV6761@disturbed> References: <20080525190754.GD13372@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080525190754.GD13372@lst.de> Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: Christoph Hellwig Cc: xfs@oss.sgi.com On Sun, May 25, 2008 at 09:07:54PM +0200, Christoph Hellwig wrote: > iosizelog shouldn't be the same as iosize but the logarithm of it. Then > again the current biosize option doesn't make much sense to me as it > doesn't set the preferred I/O size as mentioned in the comment next to That's a hold-over from irix - biosize set the basic chunk size the cache used for mapping writes, so was effectively the size of write to use to avoid RMW cycles as well as the unit of delayed allocation. > it but rather the allocation size and thus is identical to the allocsize > option (except for the missing logarithm). It's also not documented in > Documentation/filesystems/xfs.txt or the mount manpage. So when it was first added (probably for compatibility) the allocation part was noticed and not the rest. Maybe we should hook it up to xfs_preferred_iosize() rather than allocation now that it exists... Apart from that, yes it should be the logarithm, so ACK for this minor mod... Cheers, Dave. -- Dave Chinner david@fromorbit.com