From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?iso-8859-1?q?Albrecht_Dre=DF?= Subject: Re: VFAT: slow fs corruption? [long] Date: Thu, 26 Apr 2007 19:37:54 +0200 Message-ID: <1177609074l.3249l.1l@antares.localdomain> References: <20070418230027.GD13621@kvack.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; protocol="application/pgp-signature"; boundary="=-iQtH+mHSc02CzdZdd7o9" Cc: linux-fsdevel@vger.kernel.org To: Benjamin LaHaise Return-path: Received: from smtp2.netcologne.de ([194.8.194.112]:50742 "EHLO smtp2.netcologne.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754876AbXDZRh5 (ORCPT ); Thu, 26 Apr 2007 13:37:57 -0400 In-Reply-To: <20070418230027.GD13621@kvack.org> (from bcrl@kvack.org on Thu Apr 19 01:00:27 2007) Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org --=-iQtH+mHSc02CzdZdd7o9 Content-Type: text/plain; charset=iso-8859-1; DelSp=Yes; Format=Flowed Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Ben! Thanks a lot for your comments, and sorry for the late reply, I did more te= sts =20 in the meantime... Am 19.04.07 01:00 schrieb(en) Benjamin LaHaise: > On Wed, Apr 18, 2007 at 07:58:40PM +0200, Albrecht Dre=DF wrote: > > - Are there known issues with VFAT in 2.6.11 which might lead to the > = =20 > observed problems? Were they fixed? > > - Is it possible to change the block size in ext2 to 16k (to match the = =20 > SD > card's erase block size)? >=20 > Flash cards tend to be rather flaky given that they are low cost =20 > consumergrade commodities these days. I would recommend getting a new ca= rd =20 > firstand seeing if you can still replicate the problem. I am afraid my explanation was not completely clear: I reformatted the *sam= e* =20 card which gave a lot of VFAT errors with ext2 and ran the test again. Up = to =20 now, I filled the card several times and erased it, without any problem. O= nly =20 after killing (switch power off) the system in mid-air, I had a non-clean f= s =20 and one broken file (which is not surprising, afaik), giving input/output =20 errors when I tried to read it. So my first observation, that VFAT corrupts "somehow", but ext2 doesn't, st= ill =20 seems to be valid! > Out of the box, I've had to replace 2 of 8 flash cards in the last 6 mont= hs =20 > when they showed similiarly eerie data corruption when files disappeared. Yes, I know... Unfortunately, it's not possible to get reliable data about = the =20 achievable life time. > Doing an md5sum on the device 2 times in a row and getting back different= =20 > results is Not Good. Good idea - will be the next check! Thanks, Albrecht. -- Albrecht Dre=DF - Johanna-Kirchner-Stra=DFe 13 - D-53123 Bonn (German= y) Phone (+49) 228 6199571 - mailto:albrecht.dress@arcor.de GnuPG public key: http://www.mynetcologne.de/~nc-dreszal/pubkey.asc --=-iQtH+mHSc02CzdZdd7o9 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) iD8DBQBGMONyn/9unNAn/9ERAga6AKCMEsyB92jlLWhUwSYrbuFyya2PGwCgsxWo vzM67lcYJ/KDCskOyEeH91M= =LXQL -----END PGP SIGNATURE----- --=-iQtH+mHSc02CzdZdd7o9--