From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jameson Graef Rollins Subject: Re: Bug#624343: linux-image-2.6.38-2-amd64: frequent message "bio too big device md0 (248 > 240)" in kern.log Date: Sun, 01 May 2011 18:17:06 -0700 Message-ID: <87pqo1ewa5.fsf@servo.factory.finestructure.net> References: <20110427161901.27049.31001.reportbug@servo.factory.finestructure.net> <1304051980.3105.46.camel@localhost> <8739kyf53e.fsf@servo.factory.finestructure.net> <1304294457.2833.111.camel@localhost> <4DBDFE0C.3000304@fifthhorseman.net> <1304298258.2833.125.camel@localhost> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Return-path: In-Reply-To: <1304298258.2833.125.camel@localhost> Sender: linux-raid-owner@vger.kernel.org To: Ben Hutchings , Daniel Kahn Gillmor Cc: 624343@bugs.debian.org, NeilBrown , linux-raid@vger.kernel.org List-Id: linux-raid.ids --=-=-= Content-Transfer-Encoding: quoted-printable On Mon, 02 May 2011 02:04:18 +0100, Ben Hutchings wro= te: > On Sun, 2011-05-01 at 20:42 -0400, Daniel Kahn Gillmor wrote: > So far as I'm aware, the RAID may stop working, but without loss of data > that's already on disk. What exactly does "RAID may stop working mean"? Do you mean that this bug will be triggered? The raid will refuse to do further syncs? Or do you mean something else? > > How is an admin to know which I/O capabilities to check before adding a > > device to a RAID array? When is it acceptable to mix I/O capabilities? > > Can a RAID array which is not currently being used as a backing store > > for a filesystem be assembled of unlike disks? What if it is then > > (later) used as a backing store for a filesystem? > [...] >=20 > I think the answers are: > - Not easily > - When the RAID does not have another device on top This is very upsetting to me, if it's true. It completely undermines all of my assumptions about how software raid works. Are you really saying that md with mixed disks is not possible/supported when the md device has *any* other device on top of it? This is a in fact a *very* common setup. *ALL* of my raid devices have other devices on top of them (lvm at least). In fact, the debian installer supports putting dm and/or lvm on top of md on mixed disks. If what you're saying is true then the debian installer is in big trouble. jamie. --=-=-= Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAEBCAAGBQJNvgYSAAoJEO00zqvie6q86lAP/3LtkkpHPdE6kY9kBQVlEPb+ iR+V58tBq4mKAzc8Lta3HfJCZMEiZoQveUJiJYuMtwsI9eo9ED5XDapme5GUocgN fliyUHHCwMjvwzzBwYRZxOxMPJo8VfTovf3cfJdcma3legERCb7qE3tO8daaTkSP 9e9g5BWu0RNtHapk+IkC+TFSLMzd+q9CSLmgI1jL9+GJLjaRSj8vyTdpy9Z9PlVz uXUm/cv6AF5H/+lPlKvH+dUT6diuaN1eg5ixSdkeaV5t3S2ndxC4qPUsdOqiTJOn DbLPL+DKvYwqcvEH/muAPOxQAS/dEH8qrB1hyLRODbUvXcwGmdhr3Z8GVO7nCm1U pu8VfGLyZrwx2CyDYVJK6yW7BqBWT4gBWIM/zjE4yAxJQlI2YWRv/wiWUhQ7tdrZ Y3MdOfYegTWgRLV6nmhVvNYLA1yOiOcjLTj67PWTJG/z5LiSUY9n1l8AkdgpIHLu YQhHUcO01JdkPgQapZJc+U6KY2JJWjElmMc/mzEDeIFVObMBPN7xm4ehhgsYD2yV 2QC2dJ/Vx66xvRxMv5dGALH3gqCoUs8h4CQtbUD0dFf8y2eRZjN36BA+fyRx5tBB TpQkDtqL50xPii41eHyDETyBARJNoDi5e8cxYa5XFePg+P0ASCfKn7DKsLDDp0kY qjxCc+gFIZ/WJb1WJ6Cb =gdgF -----END PGP SIGNATURE----- --=-=-=--