From: Eric Subject: Re: ext2/3/4 online defrag Date: Thu, 17 May 2007 22:11:54 -0700 Message-ID: <1179465114.7891.17.camel@eric-laptop> References: <1178770799.26695.11.camel@eric-laptop> <20070517161119.GB3230@atrey.karlin.mff.cuni.cz> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-qUoeIhFoMbE9XWxH8ffI" To: linux-ext4 Return-path: Received: from nz-out-0506.google.com ([64.233.162.237]:30172 "EHLO nz-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755050AbXERFL6 (ORCPT ); Fri, 18 May 2007 01:11:58 -0400 Received: by nz-out-0506.google.com with SMTP id r28so1212868nza for ; Thu, 17 May 2007 22:11:57 -0700 (PDT) In-Reply-To: <20070517161119.GB3230@atrey.karlin.mff.cuni.cz> Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org --=-qUoeIhFoMbE9XWxH8ffI Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Thu, 2007-05-17 at 18:11 +0200, Jan Kara wrote: > But me (and several other people > independently as I've learnt recently) have written some tools which > should result in something useful. If you're interested, you can join > prefetch-devel@googlegroups.com - it's led by one guy who is doing > defrag and stuff as his google summer of code project. Is this different from the ext4/extent-based defrag patch that's been mentioned on this list? > > *An implementation of an ext* filesystem driver can work with any > > ext2/3/4 filesystem as long as it supports the necessary revision > > (GOOD_OLD_REV or DYNAMIC_REV) and feature flags set in the filesystem. > Not sure what you mean here... The "ext2 filesystem"/"ext3 filesystem"/"ext4 filesystem" terminology was confusing to me when I first started reading about them. In my mind, it implied that those three filesystems were more different than they actually are. I think it would be more accurate to say that they are all essentially the same filesystem, and that any filesystem driver that can mount a given filesystem can mount any other ext2/3/4 filesystem of the same revision with the same feature flags set. I was asking for confirmation of this assumption, but I've since found a lot of really good documentation that has cleared up a lot of things. Thanks, Eric --=-qUoeIhFoMbE9XWxH8ffI Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQBGTTWae2L37HVup3ARAvTJAJ4m9o/GAAJW8CmO0lL6MGpAWCJPewCdHd3S cO3EKllDzj7M0cKxIlKovlw= =yleC -----END PGP SIGNATURE----- --=-qUoeIhFoMbE9XWxH8ffI--