Please see below for errors I get when trying to add internal bitmap. 2012/3/1 Bryan Mesich <bryan.mesich@xxxxxxxx>: > On Thu, Mar 01, 2012 at 07:14:38PM +0100, John Obaterspok wrote: >> Hello, >> >> Occasionally my system don't shutdown cleanly and almost all time >> mdadm kicks one of the disks on the RAID5 array. >> Is there anything I can do to help prevent this? >> >> I'm using sw raid 5 with 3 x 3TB Hitachi Deskstar (7K3000 HDS723030ALA640 64MB). >> >> -------- > > [snip...] > > I'm guessing you're trying to avoid re-syncing a 6TB array in the > event that your host goes down in an un-clean state. In that > case, I would suggest using a write-intent bitmap on the array. > If you're concerned about loss of performance when using a > bitmap, use an external bitmap that is located on another > spindle(s). okay, I'm trying to add an interal bitmap to see how much it slows down things: [root@Emperor ~]# mdadm --version mdadm - v3.2.3 - 23rd December 2011 [root@Emperor ~]# mdadm --grow --bitmap=internal /dev/md2 mdadm: failed to set internal bitmap. [root@Emperor ~]# mdadm --examine-bitmap /dev/md2 Filename : /dev/md2 Magic : 00000000 mdadm: invalid bitmap magic 0x0, the bitmap file appears to be corrupted Version : 0 mdadm: unknown bitmap version 0, either the bitmap file is corrupted or you need to upgrade your tools [root@Emperor ~]# mdadm -D /dev/md2 /dev/md2: Version : 1.2 Creation Time : Thu Jul 28 07:23:45 2011 Raid Level : raid5 Array Size : 5706313728 (5441.96 GiB 5843.27 GB) Used Dev Size : 2853156864 (2720.98 GiB 2921.63 GB) Raid Devices : 3 Total Devices : 3 Persistence : Superblock is persistent Update Time : Sat Mar 3 22:24:21 2012 State : clean Active Devices : 3 Working Devices : 3 Failed Devices : 0 Spare Devices : 0 Layout : left-symmetric Chunk Size : 512K Name : Emperor:2 (local to host Emperor) UUID : a9f823df:05acab4f:1b02cfb9:70173894 Events : 1041 Number Major Minor RaidDevice State 0 8 3 0 active sync /dev/sda3 4 8 19 1 active sync /dev/sdb3 3 8 35 2 active sync /dev/sdc3 This appears in 'dmesg' [50068.295573] mdadm: sending ioctl 1261 to a partition! [50068.295577] mdadm: sending ioctl 1261 to a partition! [50068.320235] mdadm: sending ioctl 800c0910 to a partition! [50068.320239] mdadm: sending ioctl 800c0910 to a partition! [50174.085742] scsi_verify_blk_ioctl: 76 callbacks suppressed [50174.085745] mdadm: sending ioctl 1261 to a partition! [50174.085748] mdadm: sending ioctl 1261 to a partition! [50174.086052] mdadm: sending ioctl 1261 to a partition! [50174.086056] mdadm: sending ioctl 1261 to a partition! [50174.086261] mdadm: sending ioctl 1261 to a partition! [50174.086263] mdadm: sending ioctl 1261 to a partition! [50174.091615] md2: invalid bitmap file superblock: bad magic [50174.091618] md2: bitmap file superblock: [50174.091620] magic: 00400000 [50174.091622] version: 4194320 [50174.091623] uuid: 00400020.20005fe0.00010000.00000000 [50174.091625] events: 2510791976631140352 [50174.091626] events cleared: 18014471528120321 [50174.091628] state: 00030000 [50174.091629] chunksize: 0 B [50174.091630] daemon sleep: 0s [50174.091631] sync size: 1152991873353122064 KB [50174.091633] max write behind: -1180360704 [50174.095699] mdadm: sending ioctl 1261 to a partition! [50174.095701] mdadm: sending ioctl 1261 to a partition! [50174.121531] mdadm: sending ioctl 800c0910 to a partition! [50174.121535] mdadm: sending ioctl 800c0910 to a partition! [50226.959946] scsi_verify_blk_ioctl: 76 callbacks suppressed [50226.959949] mdadm: sending ioctl 1261 to a partition! [50226.959952] mdadm: sending ioctl 1261 to a partition! -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html