Time sliced cfq ver13
PATCH 1/1 Time sliced cfq ver13
Hi,
2.6.10-rc3-mm1 patch:
2.6-BK patch:
http://www.kernel.org/pub/linux/kernel/people/axboe/patches/v2.6/2.6.10-rc3/cfq-time-slices-13.gz
Changes:
- Fixup the RCU usage. Also uncovered a bug if the process exiting was active on several disks, only the first would get kicked.
- Fix problem with CFQ as default at boot for IDE. IDE asks for the same request several times, this disturbed the CFQ max_depth logic. Check if a request is already in flight and allow it.
Signature · 1 line
Jens Axboe
PATCH 1/1 Time sliced cfq ver14
Hi,
2.6.10-rc3-mm1 patch:
2.6-BK patch:
http://www.kernel.org/pub/linux/kernel/people/axboe/patches/v2.6/2.6.10-rc3/cfq-time-slices-14.gz
Changes:
- Fix leak of queue
- Better balance when to preempt. On 8 client read workload, aggregate bandwidth would take a few seconds to build up, due to initial massive preempt generation more seeks than it should. Priority check was also reverse which showed bad results on multi-prio work loads.
- Fix reversed priority check in preemption check, oops.
Signature · 1 line
Jens Axboe
PATCH 1/1 Time sliced cfq ver17
Hi,
2.6.10-rc3-mm1 patch:
2.6-BK patch:
http://www.kernel.org/pub/linux/kernel/people/axboe/patches/v2.6/2.6.10-rc3/cfq-time-slices-17.gz
Changes:
- Kill the spare queue logic
- wait_request should not imply that queue must be allowed to allocate a request, otherwise a write could quickly flood the queue. Add must_alloc to handle that and make it one-shot.
- Turn on/off idle window based on process think time and seek time. Improve idle timer logic. The seek/think time updates toggle the idle_window flag and increase queuing depth if we disable the idle window.
- Improve SCSI requeing logic. Add request fully back into cfq queue but mark it as next service once this queue gets slice time again.
- More preemption fixes. Allow new sync io to preempt equal priority async io to improve reader fairness.
Signature · 1 line
Jens Axboe