From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932350AbWGGWPn (ORCPT ); Fri, 7 Jul 2006 18:15:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932351AbWGGWPn (ORCPT ); Fri, 7 Jul 2006 18:15:43 -0400 Received: from lucidpixels.com ([66.45.37.187]:28077 "EHLO lucidpixels.com") by vger.kernel.org with ESMTP id S932350AbWGGWPm (ORCPT ); Fri, 7 Jul 2006 18:15:42 -0400 Date: Fri, 7 Jul 2006 18:15:41 -0400 (EDT) From: Justin Piszcz X-X-Sender: jpiszcz@p34.internal.lan To: Neil Brown cc: linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org Subject: Re: Kernel 2.6.17 and RAID5 Grow Problem (critical section backup) In-Reply-To: <17582.55703.209583.446356@cse.unsw.edu.au> Message-ID: References: <17582.55703.209583.446356@cse.unsw.edu.au> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 8 Jul 2006, Neil Brown wrote: > On Friday July 7, jpiszcz@lucidpixels.com wrote: >>>> >>>> Jul 7 08:44:59 p34 kernel: [4295845.933000] raid5: reshape: not enough >>>> stripes. Needed 512 >>>> Jul 7 08:44:59 p34 kernel: [4295845.962000] md: couldn't update array >>>> info. -28 >>>> >>>> So the RAID5 reshape only works if you use a 128kb or smaller chunk size? >>>> >> >> Neil, >> >> Any comments? >> > > Yes. This is something I need to fix in the next mdadm. > You need to tell md/raid5 to increase the size of the stripe cache > before the grow can proceed. You can do this with > > echo 600 > /sys/block/md3/md/stripe_cache_size > > Then the --grow should work. The next mdadm will do this for you. > > NeilBrown > Hey! You're awake :) I am going to try it with just 64kb to prove to myself it works with that, but then I will re-create the raid5 again like I had it before and attempt it again, I did not see that documented anywhere!! Also, how do you use the --backup-file option? Nobody seems to know!