]> err.no Git - linux-2.6/commit
cfq-iosched: improve preemption for cooperating tasks
authorJens Axboe <jens.axboe@oracle.com>
Wed, 14 Feb 2007 18:59:49 +0000 (19:59 +0100)
committerJens Axboe <axboe@nelson.home.kernel.dk>
Mon, 30 Apr 2007 07:01:21 +0000 (09:01 +0200)
commit1e3335de05da3dfbe48b8caa03db1834a2133256
tree3783ea1ef788f564a78754906dc508ac66595b75
parentb9099ff63c75216d6ca10bce5a1abcd9293c27e6
cfq-iosched: improve preemption for cooperating tasks

When testing the syslet async io approach, I discovered that CFQ
sometimes didn't perform as well as expected. cfq_should_preempt()
needs to better check for cooperating tasks, so fix that by allowing
preemption of an equal priority queue if the recently queued request
is as good a candidate for IO as the one we are currently waiting for.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
block/cfq-iosched.c