From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Mahoney Subject: Re: read error: how to fix? Date: Mon, 10 Oct 2011 10:07:49 -0400 Message-ID: <4E92FC35.1040608@suse.de> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Cc: Helmut Hullen , linux-btrfs@vger.kernel.org To: helmut@hullen.de Return-path: In-Reply-To: List-ID: -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 10/10/2011 09:28 AM, Helmut Hullen wrote: > Hallo, David, > > Du meintest am 10.10.11: > >>> Oct 7 18:16:55 Arktur kernel: ata5.00: exception Emask 0x0 >>> SAct 0x0 SErr 0x0 action 0x0 Oct 7 18:16:55 Arktur kernel: >>> ata5.00: BMDMA2 stat 0x80d2009 Oct 7 18:16:55 Arktur kernel: >>> ata5.00: failed command: READ DMA Oct 7 18:16:55 Arktur >>> kernel: ata5.00: cmd c8/00:40:57:d0:34/00:00:00:00:00/ee tag 0 >>> dma 32768 in Oct 7 18:16:55 Arktur kernel: res >>> 51/40:40:57:d0:34/00:03:0e:00:00/fe Emask 0x9 (media error) Oct >>> 7 18:16:55 Arktur kernel: ata5.00: status: { DRDY ERR } Oct 7 >>> 18:16:55 Arktur kernel: ata5.00: error: { UNC } Oct 7 >>> 18:16:55 Arktur kernel: ata5.00: configured for UDMA/100 Oct 7 >>> 18:16:55 Arktur kernel: ata5: EH complete >>> >>> (repeating every 3 seconds) >>> >>> The files contain no valuable data (*.mpeg files, >>> reproducable). But how can I tell the disk not to use the >>> damaged sector(s)? >>> >>> On an ext2/3 system I used "badblocks" - is there some >>> comparable tool for btrfs? > >> No there isn't, but it's a good topic for a btrfs project :) > >> (I see lots of interesting problems like relocating superblocks, >> damaged allocator structures, ...) > > I've just worked again with the 2 unreadable files. > > Copying them to another partition stopped somewhere, one time/file > at about 98%, the other time at about 2%. > > I had to kill the "cp" order with "killall cp". > > The same problem with deleting: I had to use "killall rm". "I'm not > amused" ... > > And I'm curious what the system will do with the 2 unreadable > sectors. In about 1 year I have to add the next 2 TByte disk, with > "add" and "balance". Maybe I have to copy the 3-disks cluster to a > 4-disks-cluster ... I'd try replacing the SATA cable and if that doesn't fix it up, you may be out of luck. The thing is that marking sectors bad is a (pretty poor) band-aid for a much bigger problem: If you're hitting persistent read errors and re-writing the blocks doesn't fix it, your disk is already close to being completely kaput and no amount of software is going to help with that. - -Jeff - -- Jeff Mahoney SUSE Labs -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.18 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk6S/DUACgkQLPWxlyuTD7LSXgCfZDTgMjg4mc/cbRBZeYLbmlKS A08An0DoPONviCz64sYq9H9HL3Xt0ywZ =p/lR -----END PGP SIGNATURE-----