[BACK]Return to switching-sched.txt CVS log [TXT][DIR] Up to [Development] / linux-2.6-xfs / Documentation / block

File: [Development] / linux-2.6-xfs / Documentation / block / switching-sched.txt (download)

Revision 1.1, Mon May 29 16:35:25 2006 UTC (11 years, 5 months ago) by nathans.longdrop.melbourne.sgi.com
Branch: MAIN

Merge up to 2.6.17-rc5.
Merge of 2.6.x-xfs-melb:linux:26065a by kenmcd.

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