mirror of
https://github.com/adulau/aha.git
synced 2024-12-30 20:56:23 +00:00
73af994c7d
We added the ability to change a block device's IO elevator scheduler both at kernel boot and on-the-fly, but we only documented the elevator= boot parameter. Add a quick how-to on doing it on the fly. Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Jens Axboe <axboe@suse.de>
22 lines
935 B
Text
22 lines
935 B
Text
As of the Linux 2.6.10 kernel, it is now possible to change the
|
|
IO scheduler for a given block device on the fly (thus making it possible,
|
|
for instance, to set the CFQ scheduler for the system default, but
|
|
set a specific device to use the anticipatory or noop schedulers - which
|
|
can improve that device's throughput).
|
|
|
|
To set a specific scheduler, simply do this:
|
|
|
|
echo SCHEDNAME > /sys/block/DEV/queue/scheduler
|
|
|
|
where SCHEDNAME is the name of a defined IO scheduler, and DEV is the
|
|
device name (hda, hdb, sga, or whatever you happen to have).
|
|
|
|
The list of defined schedulers can be found by simply doing
|
|
a "cat /sys/block/DEV/queue/scheduler" - the list of valid names
|
|
will be displayed, with the currently selected scheduler in brackets:
|
|
|
|
# cat /sys/block/hda/queue/scheduler
|
|
noop anticipatory deadline [cfq]
|
|
# echo anticipatory > /sys/block/hda/queue/scheduler
|
|
# cat /sys/block/hda/queue/scheduler
|
|
noop [anticipatory] deadline cfq
|