[linux-2.6-block.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"
	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.

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
9361401e	1	if BLOCK
1da177e4 LT	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
1da177e4 LT	15	config IOSCHED_DEADLINE
	16	tristate "Deadline I/O scheduler"
	17	default y
	18	---help---
492af635 JA	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.
1da177e4 LT	23
	24	config IOSCHED_CFQ
	25	tristate "CFQ I/O scheduler"
	26	default y
	27	---help---
	28	The CFQ I/O scheduler tries to distribute bandwidth equally
	29	among all processes in the system. It should provide a fair
08dc8726 JA	30	and low latency working environment, suitable for both desktop
	31	and server systems.
	32
a8e14b95	33	This is the default I/O scheduler.
1da177e4	34
25bc6b07 VG	35	config CFQ_GROUP_IOSCHED
25bc6b07 VG	36	bool "CFQ Group Scheduling support"
afc24d49	37	depends on IOSCHED_CFQ && BLK_CGROUP
25bc6b07 VG	38	default n
	39	---help---
	40	Enable group IO scheduling in CFQ.
	41
131dda7f ND	42	choice
131dda7f ND	43	prompt "Default I/O scheduler"
b17fd9bc	44	default DEFAULT_CFQ
131dda7f ND	45	help
	46	Select the I/O scheduler which will be used by default for all
	47	block devices.
	48
131dda7f	49	config DEFAULT_DEADLINE
c6ea2ba7	50	bool "Deadline" if IOSCHED_DEADLINE=y
131dda7f ND	51
131dda7f ND	52	config DEFAULT_CFQ
c6ea2ba7	53	bool "CFQ" if IOSCHED_CFQ=y
131dda7f ND	54
	55	config DEFAULT_NOOP
	56	bool "No-op"
	57
	58	endchoice
	59
	60	config DEFAULT_IOSCHED
	61	string
131dda7f ND	62	default "deadline" if DEFAULT_DEADLINE
	63	default "cfq" if DEFAULT_CFQ
	64	default "noop" if DEFAULT_NOOP
	65
1da177e4	66	endmenu
9361401e DH	67
9361401e DH	68	endif