From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from plane.gmane.org ([80.91.229.3]:41030 "EHLO plane.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752450Ab3ESS7R (ORCPT ); Sun, 19 May 2013 14:59:17 -0400 Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1Ue8p7-0002Nt-E2 for linux-btrfs@vger.kernel.org; Sun, 19 May 2013 20:59:13 +0200 Received: from cpc21-stap10-2-0-cust974.12-2.cable.virginmedia.com ([86.0.163.207]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sun, 19 May 2013 20:59:13 +0200 Received: from m_btrfs by cpc21-stap10-2-0-cust974.12-2.cable.virginmedia.com with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Sun, 19 May 2013 20:59:13 +0200 To: linux-btrfs@vger.kernel.org From: Martin Subject: Re: btrfs (general) raid for other filesystems? Date: Sun, 19 May 2013 19:59:03 +0100 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 In-Reply-To: Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 19/05/13 18:39, Clemens Eisserer wrote: > Hi Martin, > >> So, an interesting variation could be to have filesystem level raid >> operating on ext4 or nilfs or whatever... Would that be a sensible idea? > > Thats already supported by using LVM. What do you think you would gain > from layering in top of btrfs? md-raid and lvm-raid are raid at the block level. btrfs-raid offers a greater variety and far greater flexibility of raid options individually for filedata and metadata at the filesystem level. raid at the filesystem level should also gain higher performance over that of just blindly replicating blocks of binary data across devices at the block level. My thoughts are to take advantage of the btrfs-raid work being done but for all filesystems. Hence, we can then have a very flexible raid available for whatever filesystem might be best for any underlying device. OK... So we make all of lvm, md-raid, and drbd all redundant! Regards, Martin