blob: fa95fa77057071687af031435be6cf0864bf723a [file] [log] [blame]
David Howells93614012006-09-30 20:45:40 +02001if BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -07002
3menu "IO Schedulers"
4
5config 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
Linus Torvalds1da177e2005-04-16 15:20:36 -070015config IOSCHED_DEADLINE
16 tristate "Deadline I/O scheduler"
17 default y
18 ---help---
Jens Axboe492af632009-10-03 09:37:51 +020019 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.
Linus Torvalds1da177e2005-04-16 15:20:36 -070023
24config 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
Jens Axboe08dc8722009-10-03 09:40:47 +020030 and low latency working environment, suitable for both desktop
31 and server systems.
32
Jesper Juhla8e14b92007-02-17 20:08:22 +010033 This is the default I/O scheduler.
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
Vivek Goyal25bc6b02009-12-03 12:59:43 -050035config CFQ_GROUP_IOSCHED
36 bool "CFQ Group Scheduling support"
37 depends on IOSCHED_CFQ && CGROUPS
38 select BLK_CGROUP
39 default n
40 ---help---
41 Enable group IO scheduling in CFQ.
42
Nate Diller131dda72005-10-30 15:02:19 -080043choice
44 prompt "Default I/O scheduler"
Jens Axboeb17fd9b2006-06-19 10:06:48 +020045 default DEFAULT_CFQ
Nate Diller131dda72005-10-30 15:02:19 -080046 help
47 Select the I/O scheduler which will be used by default for all
48 block devices.
49
Nate Diller131dda72005-10-30 15:02:19 -080050 config DEFAULT_DEADLINE
Jens Axboec6ea2ba2005-11-04 08:44:58 +010051 bool "Deadline" if IOSCHED_DEADLINE=y
Nate Diller131dda72005-10-30 15:02:19 -080052
53 config DEFAULT_CFQ
Jens Axboec6ea2ba2005-11-04 08:44:58 +010054 bool "CFQ" if IOSCHED_CFQ=y
Nate Diller131dda72005-10-30 15:02:19 -080055
56 config DEFAULT_NOOP
57 bool "No-op"
58
59endchoice
60
61config DEFAULT_IOSCHED
62 string
Nate Diller131dda72005-10-30 15:02:19 -080063 default "deadline" if DEFAULT_DEADLINE
64 default "cfq" if DEFAULT_CFQ
65 default "noop" if DEFAULT_NOOP
66
Linus Torvalds1da177e2005-04-16 15:20:36 -070067endmenu
David Howells93614012006-09-30 20:45:40 +020068
69endif