Commit | Line | Data |
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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 |
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 | ||
2868ef7b VG |
43 | config DEBUG_CFQ_IOSCHED |
44 | bool "Debug CFQ Scheduling" | |
45 | depends on CFQ_GROUP_IOSCHED | |
46 | select DEBUG_BLK_CGROUP | |
47 | default n | |
48 | ---help--- | |
49 | Enable CFQ IO scheduling debugging in CFQ. Currently it makes | |
50 | blktrace output more verbose. | |
51 | ||
131dda7f ND |
52 | choice |
53 | prompt "Default I/O scheduler" | |
b17fd9bc | 54 | default DEFAULT_CFQ |
131dda7f ND |
55 | help |
56 | Select the I/O scheduler which will be used by default for all | |
57 | block devices. | |
58 | ||
131dda7f | 59 | config DEFAULT_DEADLINE |
c6ea2ba7 | 60 | bool "Deadline" if IOSCHED_DEADLINE=y |
131dda7f ND |
61 | |
62 | config DEFAULT_CFQ | |
c6ea2ba7 | 63 | bool "CFQ" if IOSCHED_CFQ=y |
131dda7f ND |
64 | |
65 | config DEFAULT_NOOP | |
66 | bool "No-op" | |
67 | ||
68 | endchoice | |
69 | ||
70 | config DEFAULT_IOSCHED | |
71 | string | |
131dda7f ND |
72 | default "deadline" if DEFAULT_DEADLINE |
73 | default "cfq" if DEFAULT_CFQ | |
74 | default "noop" if DEFAULT_NOOP | |
75 | ||
1da177e4 | 76 | endmenu |
9361401e DH |
77 | |
78 | endif |