Alan D. Brunelle
ac9fafa124
block: Skip I/O merges when disabled ...
The block I/O + elevator + I/O scheduler code spend a lot of time trying
to merge I/Os -- rightfully so under "normal" circumstances. However,
if one were to know that the incoming I/O stream was /very/ random in
nature, the cycles are wasted.
This patch adds a per-request_queue tunable that (when set) disables
merge attempts (beyond the simple one-hit cache check), thus freeing up
a non-trivial amount of CPU cycles.
Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:55 +02:00
block: kill swap_io_context()
2008-02-01 11:34:49 +01:00
block: rename and export rq_init()
2008-04-29 14:48:55 +02:00
block: add large command support
2008-04-29 14:48:55 +02:00
block: make core bits checkpatch compliant
2008-02-01 09:26:33 +01:00
cfq-iosched: add hlist for browsing parallel to the radix tree
2008-02-19 10:04:00 +01:00
block: add dma alignment and padding support to blk_rq_map_kern
2008-04-29 09:50:34 +02:00
block: make queue flags non-atomic
2008-04-29 14:48:33 +02:00
block: make queue flags non-atomic
2008-04-29 14:48:33 +02:00
block: Skip I/O merges when disabled
2008-04-29 14:48:55 +02:00
block: make queue flags non-atomic
2008-04-29 14:48:33 +02:00
block: rename and export rq_init()
2008-04-29 14:48:55 +02:00
blktrace: Add blktrace ioctls to SCSI generic devices
2008-01-28 10:04:46 +01:00
[SCSI] bsg: add release callback support
2008-04-22 15:16:32 -05:00
cfq-iosched: do not leak ioc_data across iosched switches
2008-04-10 08:28:01 +02:00
ide: remove broken/dangerous HDIO_[UNREGISTER,SCAN]_HWIF ioctls (take 3)
2008-04-18 00:46:24 +02:00
block: let elv_register() return void
2007-12-18 08:29:28 +01:00
block: Skip I/O merges when disabled
2008-04-29 14:48:55 +02:00
genhd must_check warning fix
2008-03-12 12:34:37 -07:00
compat_ioctl: move common block ioctls to compat_blkdev_ioctl
2007-10-10 09:26:00 +02:00
Kconfig: clean up block/Kconfig help descriptions
2008-04-21 09:51:04 +02:00
update I/O sched Kconfig help texts - CFQ is now default, not AS.
2007-02-17 20:08:22 +01:00
block: ll_rw_blk.c split, add blk-merge.c
2008-01-29 21:55:12 +01:00
block: let elv_register() return void
2007-12-18 08:29:28 +01:00
block: no need to initialize rq->cmd with blk_get_request
2008-04-29 14:48:55 +02:00
ac9fafa124