linux/Documentation/block
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
..
00-INDEX block: update documentation for REQ_FLUSH / REQ_FUA 2010-09-10 12:35:37 +02:00
biodoc.txt Fix common misspellings 2011-03-31 11:26:23 -03:00
capability.txt genhd: expose AN to user space 2007-05-23 20:14:11 -07:00
cfq-iosched.txt cfq-iosched: Documentation help for new tunables 2010-08-23 12:25:29 +02:00
data-integrity.txt Trivial typo fixes in Documentation/block/data-integrity.txt. 2009-07-01 10:56:25 +02:00
deadline-iosched.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
ioprio.txt Update Jens Axboe's email in Documentation/* 2007-10-16 09:59:55 +02:00
queue-sysfs.txt block: strict rq_affinity 2011-07-23 20:44:25 +02:00
request.txt Update Jens Axboe's email in Documentation/* 2007-10-16 09:59:55 +02:00
stat.txt
switching-sched.txt Documentation: remove anticipatory scheduler info 2010-11-11 12:09:59 +01:00
writeback_cache_control.txt block: update documentation for REQ_FLUSH / REQ_FUA 2010-09-10 12:35:37 +02:00