linux/include
Dan Williams 5757a6d76c block: strict rq_affinity
Some systems benefit from completions always being steered to the strict
requester cpu rather than the looser "per-socket" steering that
blk_cpu_to_group() attempts by default. This is because the first
CPU in the group mask ends up being completely overloaded with work,
while the others (including the original submitter) has power left
to spare.

Allow the strict mode to be set by writing '2' to the sysfs control
file. This is identical to the scheme used for the nomerges file,
where '2' is a more aggressive setting than just being turned on.

echo 2 > /sys/block/<bdev>/queue/rq_affinity

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Roland Dreier <roland@purestorage.com>
Tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-07-23 20:44:25 +02:00
..
acpi Merge branches 'acpica', 'aml-custom', 'bugzilla-16548', 'bugzilla-20242', 'd3-cold', 'ec-asus' and 'thermal-fix' into release 2011-05-29 04:38:48 -04:00
asm-generic Merge branches 'gpio/merge' and 'spi/merge' of git://git.secretlab.ca/git/linux-2.6 2011-06-17 10:36:32 -07:00
crypto
drm drm/radeon: workaround a hw bug on some radeon chipsets with all-0 EDIDs. 2011-06-16 16:30:54 +10:00
keys
linux block: strict rq_affinity 2011-07-23 20:44:25 +02:00
math-emu
media [media] v4l: Fix media_entity_to_video_device macro argument name 2011-06-01 09:42:03 -03:00
mtd
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2011-06-20 20:10:18 -07:00
pcmcia
rdma Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband 2011-05-26 12:13:57 -07:00
rxrpc
scsi [SCSI] libsas: Add option for SATA soft reset 2011-05-26 22:49:33 -05:00
sound ASoC: Remove unused and about to be broken SND_SOC_CUSTOM I/O bus 2011-06-13 19:17:55 +01:00
target [SCSI] target: Convert REPORT_LUNs to use int_to_scsilun 2011-05-24 13:02:42 -04:00
trace Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 2011-06-21 10:22:35 -07:00
video Merge branches 'common/fbdev' and 'common/fbdev-meram' of master.kernel.org:/pub/scm/linux/kernel/git/lethal/sh-2.6 2011-05-24 15:49:57 +09:00
xen Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem 2011-05-26 10:50:56 -07:00
Kbuild