From mboxrd@z Thu Jan 1 00:00:00 1970 From: Goswin von Brederlow Subject: Re: mdadm can't reshape/resize arrays Date: Thu, 25 Jun 2009 10:20:53 +0200 Message-ID: <87fxdopvve.fsf@frosties.localdomain> References: <878wjh4qt1.fsf@frosties.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: In-Reply-To: (NeilBrown's message of "Thu, 25 Jun 2009 08:07:13 +1000 (EST)") Sender: linux-raid-owner@vger.kernel.org To: NeilBrown Cc: Goswin von Brederlow , linux raid List-Id: linux-raid.ids "NeilBrown" writes: > On Thu, June 25, 2009 1:03 am, Goswin von Brederlow wrote: >> Hi, >> >> I'm trying to resize/reshape some of my arrays: >> >> md1 : active raid1 sdc5[1] >> 9767424 blocks [2/1] [_U] >> bitmap: 48/150 pages [192KB], 32KB chunk >> >> % mdadm --grow --size max /dev/md1 >> mdadm: Cannot set device size for /dev/md1: Device or resource busy >> >> and dmesg says: >> md: couldn't update array info. -16 >> >> >> md2 : active raid5 sdc2[6](S) sde2[3] sdg1[1] sdf3[4] sdd1[5] sdb1[2] >> sda1[0] >> 945625280 blocks level 5, 64k chunk, algorithm 2 [6/6] [UUUUUU] >> bitmap: 0/181 pages [0KB], 512KB chunk >> >> % mdadm --grow -n 7 /dev/md2 >> mdadm: Need to backup 1920K of critical section.. >> mdadm: Cannot set device size/shape for /dev/md2: Device or resource busy >> >> and dmesg says: >> md: couldn't update array info. -16 >> >> >> % uname -a >> Linux frosties 2.6.29.4-frosties-1 #8 Sun Jun 7 00:48:55 CEST 2009 x86_64 >> GNU/Linux >> >> % mdadm --version >> mdadm - v2.6.9 - 10th March 2009 >> >> >> Anyone have an idea what is wrong there? > > md cannot grow arrays with bitmaps as it is not able to grow the bitmap. > You need to remove the bitmap, grow the array, then add the bitmap. > And unfortunately you cannot add the bitmap until the grow > has finished. > > Yes, there is room for improvement here. > > NeilBrown Most notably that mdadm catches that and gives a sensible error. Thanks. MfG Goswin