kernel-ark/drivers/md
NeilBrown 22dfdf5212 [PATCH] md: improve read speed to raid10 arrays using 'far copies'
raid10 has two different layouts.  One uses near-copies (so multiple
copies of a block are at the same or similar offsets of different
devices) and the other uses far-copies (so multiple copies of a block
are stored a greatly different offsets on different devices).  The point
of far-copies is that it allows the first section (normally first half)
to be layed out in normal raid0 style, and thus provide raid0 sequential
read performance.

Unfortunately, the read balancing in raid10 makes some poor decisions
for far-copies arrays and you don't get the desired performance.  So
turn off that bad bit of read_balance for far-copies arrays.

With this patch, read speed of an 'f2' array is comparable with a raid0
with the same number of devices, though write speed is ofcourse still
very slow.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-28 14:42:25 -08:00
..
raid6test
bitmap.c [PATCH] md: don't pass a NULL file* into ->prepare_write() 2005-11-18 07:49:46 -08:00
dm-bio-list.h [PATCH] device-mapper snapshot: bio_list fix 2005-11-22 09:14:31 -08:00
dm-bio-record.h
dm-crypt.c
dm-emc.c
dm-exception-store.c
dm-hw-handler.c
dm-hw-handler.h
dm-io.c
dm-io.h
dm-ioctl.c [PATCH] device-mapper: list_versions fix 2005-11-22 09:14:31 -08:00
dm-linear.c
dm-log.c [PATCH] device-mapper: mirror log bitset fix 2005-11-22 09:14:31 -08:00
dm-log.h
dm-mpath.c [PATCH] device-mapper dm-mpath: endio spinlock fix 2005-11-22 09:14:31 -08:00
dm-mpath.h
dm-path-selector.c
dm-path-selector.h
dm-raid1.c [PATCH] device-mapper raid1: drop mark_region spinlock fix 2005-11-22 09:14:31 -08:00
dm-round-robin.c
dm-snap.c
dm-snap.h
dm-stripe.c
dm-table.c
dm-target.c
dm-zero.c
dm.c
dm.h
faulty.c
Kconfig
kcopyd.c
kcopyd.h
linear.c
Makefile
md.c [PATCH] md: fix is_mddev_idle calculation now that disk/sector accounting happens when request completes 2005-11-18 07:49:46 -08:00
mktables.c
multipath.c [PATCH] md: convert 'faulty' and 'in_sync' fields to bits in 'flags' field 2005-11-09 07:56:38 -08:00
raid0.c
raid1.c [PATCH] md: make manual repair work for raid1 2005-11-09 07:56:39 -08:00
raid5.c [PATCH] md: fix some locking and module refcounting issues with md's use of sysfs 2005-11-09 07:56:39 -08:00
raid6.h
raid6algos.c
raid6altivec.uc
raid6int.uc
raid6main.c [PATCH] md: convert 'faulty' and 'in_sync' fields to bits in 'flags' field 2005-11-09 07:56:38 -08:00
raid6mmx.c
raid6recov.c
raid6sse1.c
raid6sse2.c
raid6x86.h
raid10.c [PATCH] md: improve read speed to raid10 arrays using 'far copies' 2005-11-28 14:42:25 -08:00
unroll.pl
xor.c