tree 757ebcc4da3ba7b8d8beb8e8e0ff6a4fe4428f52
parent 2b876f95d03e226394b5d360c86127cbefaf614b
author Corrado Zoccolo <czoccolo@gmail.com> 1260096532 +0100
committer Jens Axboe <axboe@carl.(none)> 1260358375 +0100

cfq-iosched: reduce write depth only if sync was delayed

The introduction of ramp-up formula for async queue depths has
slowed down dirty page reclaim, by reducing async write performance.
This patch makes sure the formula kicks in only when sync request
was recently delayed.

Signed-off-by: Corrado Zoccolo <czoccolo@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>