Robert Becker 1e50915fe0 raid: improve MD/raid10 handling of correctable read errors. ... We've noticed severe lasting performance degradation of our raid arrays when we have drives that yield large amounts of media errors. The raid10 module will queue each failed read for retry, and also will attempt call fix_read_error() to perform the read recovery. Read recovery is performed while the array is frozen, so repeated recovery attempts can degrade the performance of the array for extended periods of time. With this patch I propose adding a per md device max number of corrected read attempts. Each rdev will maintain a count of read correction attempts in the rdev->read_errors field (not used currently for raid10). When we enter fix_read_error() we'll check to see when the last read error occurred, and divide the read error count by 2 for every hour since the last read error. If at that point our read error count exceeds the read error threshold, we'll fail the raid device. In addition in this patch I add sysfs nodes (get/set) for the per md max_read_errors attribute, the rdev->read_errors attribute, and added some printk's to indicate when fix_read_error fails to repair an rdev. For testing I used debugfs->fail_make_request to inject IO errors to the rdev while doing IO to the raid array. Signed-off-by: Robert Becker <Rob.Becker@riverbed.com> Signed-off-by: NeilBrown <neilb@suse.de>		2009-12-14 12:51:41 +11:00
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raid6test	md: drivers/md/unroll.pl replaced with awk analog	2009-10-16 16:25:19 +11:00
.gitignore
bitmap.c	md/bitmap: update dirty flag when bitmap bits are explicitly set.	2009-12-14 12:51:41 +11:00
bitmap.h	md: Support write-intent bitmaps with externally managed metadata.	2009-12-14 12:51:41 +11:00
dm-bio-record.h	dm: preserve bi_io_vec when resubmitting bios	2009-04-02 19:55:23 +01:00
dm-crypt.c	tree-wide: fix a very frequent spelling mistake	2009-11-09 09:40:54 +01:00
dm-delay.c	dm table: pass correct dev area size to device_area_is_valid	2009-07-23 20:30:42 +01:00
dm-exception-store.c	dm snapshot: allow chunk size to be less than page size	2009-10-16 23:18:22 +01:00
dm-exception-store.h	dm snapshot: use unsigned integer chunk size	2009-10-16 23:18:17 +01:00
dm-io.c	dm io: retry after barrier error	2009-06-22 10:12:26 +01:00
dm-ioctl.c	Driver-Core: extend devnode callbacks to provide permissions	2009-09-19 12:50:38 -07:00
dm-kcopyd.c	dm kcopyd: fix callback race	2009-04-09 00:27:17 +01:00
dm-linear.c	dm table: pass correct dev area size to device_area_is_valid	2009-07-23 20:30:42 +01:00
dm-log-userspace-base.c	dm log: userspace fix incorrect luid cast in userspace_ctr	2009-10-16 23:18:15 +01:00
dm-log-userspace-transfer.c	dm/connector: Only process connector packages from privileged processes	2009-10-02 10:54:10 -07:00
dm-log-userspace-transfer.h	dm log: userspace add luid to distinguish between concurrent log instances	2009-09-04 20:40:34 +01:00
dm-log.c	dm log: fix create_log_context to use logical_block_size of log device	2009-06-22 10:12:33 +01:00
dm-mpath.c	[SCSI] scsi_dh: Change the scsidh_activate interface to be asynchronous	2009-12-04 12:00:46 -06:00
dm-mpath.h	dm mpath: remove is_active from struct dm_path	2008-10-10 13:36:58 +01:00
dm-path-selector.c	dm: path selector use module refcount directly	2009-04-02 19:55:27 +01:00
dm-path-selector.h	dm mpath: add start_io and nr_bytes to path selectors	2009-06-22 10:12:27 +01:00
dm-queue-length.c	dm mpath: add queue length load balancer	2009-06-22 10:12:27 +01:00
dm-raid1.c	bio: first step in sanitizing the bio->bi_rw flag testing	2009-09-11 14:33:31 +02:00
dm-region-hash.c	dm raid1: keep retrying alloc if mempool_alloc failed	2009-06-22 10:12:13 +01:00
dm-round-robin.c	dm mpath: add start_io and nr_bytes to path selectors	2009-06-22 10:12:27 +01:00
dm-service-time.c	dm mpath: add service time load balancer	2009-06-22 10:12:28 +01:00
dm-snap-persistent.c	dm snapshot: use unsigned integer chunk size	2009-10-16 23:18:17 +01:00
dm-snap-transient.c	dm snapshot: move status to exception store	2009-04-02 19:55:35 +01:00
dm-snap.c	dm snapshot: use unsigned integer chunk size	2009-10-16 23:18:17 +01:00
dm-stripe.c	block: Optimal I/O limit wrapper	2009-09-14 08:24:52 +02:00
dm-sysfs.c	dm: sysfs add suspended attribute	2009-06-22 10:12:29 +01:00
dm-table.c	dm stripe: expose correct io hints	2009-09-04 20:40:25 +01:00
dm-target.c	dm target: remove struct tt_internal	2009-04-02 19:55:28 +01:00
dm-uevent.c	md: replace remaining __FUNCTION__ occurrences	2008-04-28 08:58:42 -07:00
dm-uevent.h	dm: uevent generate events	2007-10-20 02:01:26 +01:00
dm-zero.c	dm: consolidate target deregistration error handling	2009-01-06 03:04:58 +00:00
dm.c	dm: dec_pending needs locking to save error value	2009-10-16 23:18:15 +01:00
dm.h	dm: remove queue next_ordered workaround for barriers	2009-07-23 20:30:40 +01:00
faulty.c	md: Move check for bitmap presence to personality code.	2009-06-18 08:49:23 +10:00
Kconfig	Merge branch 'dmaengine' into async-tx-next	2009-09-08 17:55:21 -07:00
linear.c	md: support barrier requests on all personalities.	2009-12-14 12:49:49 +11:00
linear.h	md/linear: use call_rcu to free obsolete 'conf' structures.	2009-06-18 08:49:42 +10:00
Makefile	md: drivers/md/unroll.pl replaced with awk analog	2009-10-16 16:25:19 +11:00
md.c	raid: improve MD/raid10 handling of correctable read errors.	2009-12-14 12:51:41 +11:00
md.h	raid: improve MD/raid10 handling of correctable read errors.	2009-12-14 12:51:41 +11:00
mktables.c	md/raid6: move raid6 data processing to raid6_pq.ko	2009-03-31 15:09:39 +11:00
multipath.c	md: support barrier requests on all personalities.	2009-12-14 12:49:49 +11:00
multipath.h	md: remove mddev_to_conf "helper" macro	2009-06-16 16:54:21 +10:00
raid0.c	md: support barrier requests on all personalities.	2009-12-14 12:49:49 +11:00
raid0.h	md: remove mddev_to_conf "helper" macro	2009-06-16 16:54:21 +10:00
raid1.c	md: move offset, daemon_sleep and chunksize out of bitmap structure	2009-12-14 12:51:41 +11:00
raid1.h	md/raid1: add takeover support for raid5->raid1	2009-12-14 12:51:41 +11:00
raid5.c	md/raid5: don't complete make_request on barrier until writes are scheduled	2009-12-14 12:51:40 +11:00
raid5.h	md: fix problems with RAID6 calculations for DDF.	2009-10-16 16:27:34 +11:00
raid6algos.c	md: remove sparse warning:symbol XXX was not declared.	2009-12-14 12:49:47 +11:00
raid6altivec.uc	md: drivers/md/unroll.pl replaced with awk analog	2009-10-16 16:25:19 +11:00
raid6int.uc	md: drivers/md/unroll.pl replaced with awk analog	2009-10-16 16:25:19 +11:00
raid6mmx.c	md/raid6: move raid6 data processing to raid6_pq.ko	2009-03-31 15:09:39 +11:00
raid6recov.c	md/raid6: move raid6 data processing to raid6_pq.ko	2009-03-31 15:09:39 +11:00
raid6sse1.c	md/raid6: move raid6 data processing to raid6_pq.ko	2009-03-31 15:09:39 +11:00
raid6sse2.c	md/raid6: move raid6 data processing to raid6_pq.ko	2009-03-31 15:09:39 +11:00
raid6x86.h	md: fix typo in FSF address	2009-03-31 14:57:37 +11:00
raid10.c	raid: improve MD/raid10 handling of correctable read errors.	2009-12-14 12:51:41 +11:00
raid10.h	md: remove mddev_to_conf "helper" macro	2009-06-16 16:54:21 +10:00
unroll.awk	md: drivers/md/unroll.pl replaced with awk analog	2009-10-16 16:25:19 +11:00