Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759269Ab1FWLCg (ORCPT ); Thu, 23 Jun 2011 07:02:36 -0400 Received: from mx3.schottelius.org ([77.109.138.221]:36564 "EHLO mx3.schottelius.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759224Ab1FWLCf (ORCPT ); Thu, 23 Jun 2011 07:02:35 -0400 X-Greylist: delayed 533 seconds by postgrey-1.27 at vger.kernel.org; Thu, 23 Jun 2011 07:02:35 EDT Date: Thu, 23 Jun 2011 12:53:37 +0200 From: Nico Schottelius To: LKML Subject: Mis-Design of Btrfs? Message-ID: <20110623105337.GD3753@ethz.ch> Mail-Followup-To: Nico Schottelius , LKML MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: echo $message | gpg -e $sender -s | netcat mailhost 25 X-Netzseite: http://www.nico.schottelius.org/ X-System-Info: kr (Linux 2.6.39-ARCH x86_64) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1306 Lines: 34 Good morning devs, I'm wondering whether the raid- and volume-management-builtin of btrfs is actually a sane idea or not. Currently we do have md/device-mapper support for raid already, btrfs lacks raid5 support and re-implements stuff that has already been done. I'm aware of the fact that it is very useful to know on which devices we are in a filesystem. But I'm wondering, whether it wouldn't be smarter to generalise the information exposure through the VFS layer instead of replicating functionality: Physical: USB-HD SSD USB-Flash | Exposes information to Raid: Raid1, Raid5, Raid10, etc. | higher levels Crypto: Luks | LVM: Groups/Volumes | FS: xfs/jfs/reiser/ext3 v Thus a filesystem like ext3 could be aware that it is running on a USB HD, enable -o sync be default or have the filesystem to rewrite blocks when running on crypto or optimise for an SSD, ... Cheers, Nico -- PGP key: 7ED9 F7D3 6B10 81D7 0EC5 5C09 D7DC C8E4 3187 7DF0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/