From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Mario 'BitKoenig' Holbe" Subject: Re: Incorrect in-kernel bitmap on raid10 Date: Sun, 3 May 2009 15:22:30 +0200 Message-ID: <20090503132230.GA23302@darkside.22.kls.lan> References: <18922.50050.860008.242658@notabene.brown> <18938.23135.726382.733302@notabene.brown> <20090501175524.GA8163@darkside.22.kls.lan> <20090502195259.GA8499@darkside.22.kls.lan> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="BOKacYhQ+x31HxR3" Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: NeilBrown Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids --BOKacYhQ+x31HxR3 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun, May 03, 2009 at 08:41:49AM +1000, NeilBrown wrote: > I managed to reproduce this thanks to all the detail you provided. > The problem was caused by trying to add a device to the array while the > array was readonly. Okay, I understand. I was just trying to find a way to sync all the spares simultaneously. > Can you duplicated the problem without setting the array to readonly? No, mdadm -A /dev/md7; mdadm --add /dev/md7 /dev/sd[fgh]1 seems to respect the bitmap, but first adds the first spare only and the two remaining spares when the first resync has been finished. According to your previous mail, I will run into your case 3/ this way, the bug where the bitmap is cleared too early, will I? I'm very willing to test your announced patch :) > Yes, it would be nice to be able to add multiple devices at once. > Maybe I could just get the kernel to wait 100ms after an add before This is probably the easiest way to work around this issue on the short run. However, such kind of timeouts cry for race conditions. Perhaps, allowing to add spares in read-only mode or some flag like "wait for confirmation before starting to resync" would be a cleaner approach on the long run. Thank you very much for your help Mario --=20 Gemuese schmeckt am besten, wenn man es kurz vor dem Verzehr durch ein Schnitzel ersetzt! --BOKacYhQ+x31HxR3 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iQEVAwUBSf2alhS+e2HeSPbpAQIEbgf+Oq+QfPez1pCow/BpFixox1+9ixEP9KYW Sw7G+zLImS5gnolQeg/rm0OpDkdOPcredbkX63fpjux6yqJYL/jT7H1KKnBH7PhX WsVW7cBs/AkgUgoKJbzzf9xwIcGQbBlZyQtcIxl6TtA9vfhT2cTCtCT9sZ47va0N x6+39LX1yhIYPUFPyPcsfTLA17pLWU2EMnbGTRgE7gLfeL8j45A+Xk8OF2XJYhoC e/GRPIo2iAj4t9lLeMA9t/0VwuZTmmhCsOu7Gaj1aR2DZQ8Bjj1e8zjakEiWyDVV pslGBw9EBAkEEvjw1KLUb10AGhGzKUmXoUr7c8ANDrv+WKlmHPY5tw== =8Gpb -----END PGP SIGNATURE----- --BOKacYhQ+x31HxR3--