[mirror_ubuntu-zesty-kernel.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_AS
	tristate "Anticipatory I/O scheduler"
	default y
	---help---
	  The anticipatory I/O scheduler is the default disk scheduler. It is
	  generally a good choice for most environments, but is quite large and
	  complex when compared to the deadline I/O scheduler, it can also be
	  slower in some cases especially some database loads.

config IOSCHED_DEADLINE
	tristate "Deadline I/O scheduler"
	default y
	---help---
	  The deadline I/O scheduler is simple and compact, and is often as
	  good as the anticipatory I/O scheduler, and in some database
	  workloads, better. In the case of a single process performing I/O to
	  a disk at any one time, its behaviour is almost identical to the
	  anticipatory I/O scheduler and so is a good choice.

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
	  working environment, suitable for desktop systems.

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_AS
		bool "Anticipatory" if IOSCHED_AS=y

	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 "anticipatory" if DEFAULT_AS
	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
	15	config IOSCHED_AS
	16	tristate "Anticipatory I/O scheduler"
	17	default y
	18	---help---
	19	The anticipatory I/O scheduler is the default disk scheduler. It is
	20	generally a good choice for most environments, but is quite large and
	21	complex when compared to the deadline I/O scheduler, it can also be
	22	slower in some cases especially some database loads.
	23
	24	config IOSCHED_DEADLINE
	25	tristate "Deadline I/O scheduler"
	26	default y
	27	---help---
	28	The deadline I/O scheduler is simple and compact, and is often as
	29	good as the anticipatory I/O scheduler, and in some database
	30	workloads, better. In the case of a single process performing I/O to
	31	a disk at any one time, its behaviour is almost identical to the
	32	anticipatory I/O scheduler and so is a good choice.
	33
	34	config IOSCHED_CFQ
	35	tristate "CFQ I/O scheduler"
	36	default y
	37	---help---
	38	The CFQ I/O scheduler tries to distribute bandwidth equally
	39	among all processes in the system. It should provide a fair
	40	working environment, suitable for desktop systems.
	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
	49	config DEFAULT_AS
c6ea2ba7	50	bool "Anticipatory" if IOSCHED_AS=y
131dda7f ND	51
131dda7f ND	52	config DEFAULT_DEADLINE
c6ea2ba7	53	bool "Deadline" if IOSCHED_DEADLINE=y
131dda7f ND	54
131dda7f ND	55	config DEFAULT_CFQ
c6ea2ba7	56	bool "CFQ" if IOSCHED_CFQ=y
131dda7f ND	57
	58	config DEFAULT_NOOP
	59	bool "No-op"
	60
	61	endchoice
	62
	63	config DEFAULT_IOSCHED
	64	string
	65	default "anticipatory" if DEFAULT_AS
	66	default "deadline" if DEFAULT_DEADLINE
	67	default "cfq" if DEFAULT_CFQ
	68	default "noop" if DEFAULT_NOOP
	69
1da177e4	70	endmenu
9361401e DH	71
9361401e DH	72	endif