forked from Minki/linux
02b35081fc
o Implement another CFQ mode where we charge group in terms of number of requests dispatched instead of measuring the time. Measuring in terms of time is not possible when we are driving deeper queue depths and there are requests from multiple cfq queues in the request queue. o This mode currently gets activated if one sets slice_idle=0 and associated disk supports NCQ. Again the idea is that on an NCQ disk with idling disabled most of the queues will dispatch 1 or more requests and then cfq queue expiry happens and we don't have a way to measure time. So start providing fairness in terms of IOPS. o Currently IOPS mode works only with cfq group scheduling. CFQ is following different scheduling algorithms for queue and group scheduling. These IOPS stats are used only for group scheduling hence in non-croup mode nothing should change. o For CFQ group scheduling one can disable slice idling so that we don't idle on queue and drive deeper request queue depths (achieving better throughput), at the same time group idle is enabled so one should get service differentiation among groups. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com> |
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| .. | ||
| blk-barrier.c | ||
| blk-cgroup.c | ||
| blk-cgroup.h | ||
| blk-core.c | ||
| blk-exec.c | ||
| blk-integrity.c | ||
| blk-ioc.c | ||
| blk-iopoll.c | ||
| blk-lib.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 | ||
| cfq.h | ||
| compat_ioctl.c | ||
| deadline-iosched.c | ||
| elevator.c | ||
| genhd.c | ||
| ioctl.c | ||
| Kconfig | ||
| Kconfig.iosched | ||
| Makefile | ||
| noop-iosched.c | ||
| scsi_ioctl.c | ||