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
16 tristate "Test I/O scheduler"
20 The test I/O scheduler is a duplicate of the noop scheduler with
21 addition of test utlity.
22 It allows testing a block device by dispatching specific requests
23 according to the test case and declare PASS/FAIL according to the
24 requests completion error code.
26 config IOSCHED_DEADLINE
27 tristate "Deadline I/O scheduler"
30 The deadline I/O scheduler is simple and compact. It will provide
31 CSCAN service with FIFO expiration of requests, switching to
32 a new point in the service tree and doing a batch of IO from there
36 tristate "CFQ I/O scheduler"
39 The CFQ I/O scheduler tries to distribute bandwidth equally
40 among all processes in the system. It should provide a fair
41 and low latency working environment, suitable for both desktop
44 This is the default I/O scheduler.
46 config CFQ_GROUP_IOSCHED
47 bool "CFQ Group Scheduling support"
48 depends on IOSCHED_CFQ && BLK_CGROUP
51 Enable group IO scheduling in CFQ.
54 tristate "Zen I/O scheduler"
57 FCFS, dispatches are back-inserted, deadlines ensure fairness.
58 Should work best with devices where there is no travel delay.
61 tristate "Maple I/O scheduler"
65 prompt "Default I/O scheduler"
68 Select the I/O scheduler which will be used by default for all
71 config DEFAULT_DEADLINE
72 bool "Deadline" if IOSCHED_DEADLINE=y
75 bool "CFQ" if IOSCHED_CFQ=y
78 bool "ZEN" if IOSCHED_ZEN=y
81 bool "Maple" if IOSCHED_MAPLE=y
88 config DEFAULT_IOSCHED
90 default "deadline" if DEFAULT_DEADLINE
91 default "cfq" if DEFAULT_CFQ
92 default "zen" if DEFAULT_ZEN
93 default "maple" if DEFAULT_MAPLE
94 default "noop" if DEFAULT_NOOP