From: Andreas Dilger Subject: Re: Ininitial e2fsprogs TODO list (please expand) Date: Wed, 16 Apr 2008 21:26:52 -0600 Message-ID: <20080417032652.GD3473@webber.adilger.int> References: <20080415115216.1f6868de@gara.konoha.net> <20080416033002.GZ3106@webber.adilger.int> <20080415233510.11f9179f@gara.konoha.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7BIT Cc: linux-ext4 To: "Jose R. Santos" Return-path: Received: from sca-es-mail-2.Sun.COM ([192.18.43.133]:60248 "EHLO sca-es-mail-2.sun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750932AbYDQD06 (ORCPT ); Wed, 16 Apr 2008 23:26:58 -0400 Received: from fe-sfbay-10.sun.com ([192.18.43.129]) by sca-es-mail-2.sun.com (8.13.7+Sun/8.12.9) with ESMTP id m3H3Qv2E027845 for ; Wed, 16 Apr 2008 20:26:57 -0700 (PDT) Received: from conversion-daemon.fe-sfbay-10.sun.com by fe-sfbay-10.sun.com (Sun Java System Messaging Server 6.2-8.04 (built Feb 28 2007)) id <0JZG000019IP5T00@fe-sfbay-10.sun.com> (original mail from adilger@sun.com) for linux-ext4@vger.kernel.org; Wed, 16 Apr 2008 20:26:57 -0700 (PDT) In-reply-to: <20080415233510.11f9179f@gara.konoha.net> Content-disposition: inline Sender: linux-ext4-owner@vger.kernel.org List-ID: On Apr 15, 2008 23:35 -0500, Jose R. Santos wrote: > On Tue, 15 Apr 2008 21:30:02 -0600 > Andreas Dilger wrote: > > Something was lost in translation here. The uninit_groups feature DOES > > zero the inode tables by default, and marks the groups with ITABLE_ZEROED. > > It is only if "-O uninit_groups,lazy_bg" are both given at the same time > > that the itable is not initialized. That is no different than if lazy_bg > > was given by itself. > > Yes, I understand this part. > > > So nothing needs to be done in e2fsprogs until some time after the kernel > > is updated to do the zeroing. > > The problem is that not initializing the inode table on the uninit > block group patch depends on a feature (lazy_bg) that Ted wants > removed. I believe that just removing the lazy_bg feature would be > enough to remove this capability from the uninit patch, but was not > entirely sure so I put the item just to keep track of it. > > If lazy_bg is in fact removed from e2fsprogs, I suppose we need to add > another item to enable lazy setup of the inode tables once the proper > support in the kernel is establish. Yes, the "lazy init" for uinint_groups will essentially be identical to what we have in lazy_bg today. So if we are disabling lazy_bg as a user-selectable option, we should leave the code in place for later use. I wouldn't object to requiring a user to specify "mke2fs -O FEATURE_C6" to enable it. That keeps it out of the hands of newbies, but leaves the capability to test large filesystems w/o 45 minute mke2fs times. Cheers, Andreas -- Andreas Dilger Sr. Staff Engineer, Lustre Group Sun Microsystems of Canada, Inc.