From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: Raid5 device hangs in active state Date: Wed, 29 Feb 2012 08:46:07 +1100 Message-ID: <20120229084607.29c63965@notabene.brown> References: <4F0A129E.5020706@nuclearwinter.com> <20120109112644.489e4a48@notabene.brown> <4F4D1B33.3010308@nuclearwinter.com> <20120229065206.60d1e2ea@notabene.brown> <4F4D4844.3010805@nuclearwinter.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/To2lif3/7X67WaaobYs2R.5"; protocol="application/pgp-signature" Return-path: In-Reply-To: <4F4D4844.3010805@nuclearwinter.com> Sender: linux-raid-owner@vger.kernel.org To: Larkin Lowrey Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids --Sig_/To2lif3/7X67WaaobYs2R.5 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Tue, 28 Feb 2012 15:33:56 -0600 Larkin Lowrey wrote: > Thank you for taking a look. >=20 > I should be able to move the drives to a completely different controller > (and driver) so that will be a good test. >=20 > Could NCQ be an issue? IOW, do you think it would be worth disabling NCQ > and re-running this scenario? >=20 At this point I wouldn't want to exclude anything as a possible issue. So anything that you can turn off or on fairly easily would be worth checking. If you turn off NCQ and the problem goes away, that isn't proof that NCQ is the problem. If it is a race condition, then removing NCQ could upset timings just enough that you stop hitting the race window. However if you get acceptable performance without NFQ then it could turn out to be an effective work-around even if it isn't the real problem. NeilBrown --Sig_/To2lif3/7X67WaaobYs2R.5 Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.18 (GNU/Linux) iQIVAwUBT01LHznsnt1WYoG5AQJ2aQ//cUbwEujBeTSUh1flTyvVDgKQq+RtpyO1 1yDsrxwROieKSFY5BUrOrskV3hRMO7Kysy6c+sMCBAeTdUOYlir9AK4nxD2X8VAH YW3PRR4e6t4wM+m4M7M1CdsH/zHNigsQ2OA42Fhk9E2KNATBj1Ww9aPt+oy8+oxW kT1sGKEjBsw9DwpcjW7PHxlesr4xNlt5JDpDvPFYVxM1nGvfpVZiOoYybmPvgUQt 7v2Ll0sHcoGf9CbnQeVvcb/EhCzG7g7Db8/xSRbVTjDKN9Byml5no/xM1gqxzD3n QCFpJV7KdHDFUWZMxJ7wboE2u7kn/mYiXok5Dsu7VvgMW8+0uJ7bIt/MS/JT3WUO vHjmR/pyZa+BEdAYDhSDIo8qibE3LPAbQv5huLCS9s3IKXVH/Vvwka4UxMckG3dI vKXg4c7eY0TUfhTM1U1IKDzARwSNMFgc+ahYoixFwGAME/y2B6pTRckBJw0qDGDi vaWQC+PNEzg1uyF6cd/szXvogKX7cKMQ2i8odfweLi8i6rnZ+mZ8pEGngQxyaurY /+XOexGzhfWyv/U72kBx3C5+F449UB3dHg8B/hrAGcsha86N0PqzVRE6Qx0rzwvg TCHcnwbXcyPOmReXuj6PrBBuAUqxiN1tVYqdC9fwJqm48gUsm+OZBkX9sl1I8bMm s2T12671Bqw= =l0vd -----END PGP SIGNATURE----- --Sig_/To2lif3/7X67WaaobYs2R.5--