mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-29 15:43:59 +08:00
718eee0579
Currently no-idle queues in cfq are not serviced fairly: even if they can only dispatch a small number of requests at a time, they have to compete with idling queues to be serviced, experiencing large latencies. We should notice, instead, that no-idle queues are the ones that would benefit most from having low latency, in fact they are any of: * processes with large think times (e.g. interactive ones like file managers) * seeky (e.g. programs faulting in their code at startup) * or marked as no-idle from upper levels, to improve latencies of those requests. This patch improves the fairness and latency for those queues, by: * separating sync idle, sync no-idle and async queues in separate service_trees, for each priority * service all no-idle queues together * and idling when the last no-idle queue has been serviced, to anticipate for more no-idle work * the timeslices allotted for idle and no-idle service_trees are computed proportionally to the number of processes in each set. Servicing all no-idle queues together should have a performance boost for NCQ-capable drives, without compromising fairness. Signed-off-by: Corrado Zoccolo <czoccolo@gmail.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com> |
||
---|---|---|
.. | ||
blk-barrier.c | ||
blk-core.c | ||
blk-exec.c | ||
blk-integrity.c | ||
blk-ioc.c | ||
blk-iopoll.c | ||
blk-map.c | ||
blk-merge.c | ||
blk-settings.c | ||
blk-softirq.c | ||
blk-sysfs.c | ||
blk-tag.c | ||
blk-timeout.c | ||
blk.h | ||
bsg.c | ||
cfq-iosched.c | ||
compat_ioctl.c | ||
deadline-iosched.c | ||
elevator.c | ||
genhd.c | ||
ioctl.c | ||
Kconfig | ||
Kconfig.iosched | ||
Makefile | ||
noop-iosched.c | ||
scsi_ioctl.c |