[net-next-2.6.git] / block / Kconfig.iosched

if BLOCK

menu "IO Schedulers"

config IOSCHED_NOOP
	bool
	default y
	---help---
	  The no-op I/O scheduler is a minimal scheduler that does basic merging
	  and sorting. Its main uses include non-disk based block devices like
	  memory devices, and specialised software or hardware environments
	  that do their own scheduling and require only minimal assistance from
	  the kernel.

config IOSCHED_DEADLINE
	tristate "Deadline I/O scheduler"
	default y
	---help---
	  The deadline I/O scheduler is simple and compact. It will provide
	  CSCAN service with FIFO expiration of requests, switching to
	  a new point in the service tree and doing a batch of IO from there
	  in case of expiry.

config IOSCHED_CFQ
	tristate "CFQ I/O scheduler"
	# If BLK_CGROUP is a module, CFQ has to be built as module.
	depends on (BLK_CGROUP=m && m) || !BLK_CGROUP || BLK_CGROUP=y
	default y
	---help---
	  The CFQ I/O scheduler tries to distribute bandwidth equally
	  among all processes in the system. It should provide a fair
	  and low latency working environment, suitable for both desktop
	  and server systems.

	  This is the default I/O scheduler.

	  Note: If BLK_CGROUP=m, then CFQ can be built only as module.

config CFQ_GROUP_IOSCHED
	bool "CFQ Group Scheduling support"
	depends on IOSCHED_CFQ && BLK_CGROUP
	default n
	---help---
	  Enable group IO scheduling in CFQ.

choice
	prompt "Default I/O scheduler"
	default DEFAULT_CFQ
	help
	  Select the I/O scheduler which will be used by default for all
	  block devices.

	config DEFAULT_DEADLINE
		bool "Deadline" if IOSCHED_DEADLINE=y

	config DEFAULT_CFQ
		bool "CFQ" if IOSCHED_CFQ=y

	config DEFAULT_NOOP
		bool "No-op"

endchoice

config DEFAULT_IOSCHED
	string
	default "deadline" if DEFAULT_DEADLINE
	default "cfq" if DEFAULT_CFQ
	default "noop" if DEFAULT_NOOP

endmenu

endif
Commit	Line	Data
	1	if BLOCK
	2
	3	menu "IO Schedulers"
	4
	5	config IOSCHED_NOOP
	6	bool
	7	default y
	8	---help---
	9	The no-op I/O scheduler is a minimal scheduler that does basic merging
	10	and sorting. Its main uses include non-disk based block devices like
	11	memory devices, and specialised software or hardware environments
	12	that do their own scheduling and require only minimal assistance from
	13	the kernel.
	14
	15	config IOSCHED_DEADLINE
	16	tristate "Deadline I/O scheduler"
	17	default y
	18	---help---
	19	The deadline I/O scheduler is simple and compact. It will provide
	20	CSCAN service with FIFO expiration of requests, switching to
	21	a new point in the service tree and doing a batch of IO from there
	22	in case of expiry.
	23
	24	config IOSCHED_CFQ
	25	tristate "CFQ I/O scheduler"
	26	# If BLK_CGROUP is a module, CFQ has to be built as module.
	27	depends on (BLK_CGROUP=m && m) \|\| !BLK_CGROUP \|\| BLK_CGROUP=y
	28	default y
	29	---help---
	30	The CFQ I/O scheduler tries to distribute bandwidth equally
	31	among all processes in the system. It should provide a fair
	32	and low latency working environment, suitable for both desktop
	33	and server systems.
	34
	35	This is the default I/O scheduler.
	36
	37	Note: If BLK_CGROUP=m, then CFQ can be built only as module.
	38
	39	config CFQ_GROUP_IOSCHED
	40	bool "CFQ Group Scheduling support"
	41	depends on IOSCHED_CFQ && BLK_CGROUP
	42	default n
	43	---help---
	44	Enable group IO scheduling in CFQ.
	45
	46	choice
	47	prompt "Default I/O scheduler"
	48	default DEFAULT_CFQ
	49	help
	50	Select the I/O scheduler which will be used by default for all
	51	block devices.
	52
	53	config DEFAULT_DEADLINE
	54	bool "Deadline" if IOSCHED_DEADLINE=y
	55
	56	config DEFAULT_CFQ
	57	bool "CFQ" if IOSCHED_CFQ=y
	58
	59	config DEFAULT_NOOP
	60	bool "No-op"
	61
	62	endchoice
	63
	64	config DEFAULT_IOSCHED
	65	string
	66	default "deadline" if DEFAULT_DEADLINE
	67	default "cfq" if DEFAULT_CFQ
	68	default "noop" if DEFAULT_NOOP
	69
	70	endmenu
	71
	72	endif