xref: /openbmc/linux/block/Kconfig.iosched (revision dea54fba)
1if BLOCK
2
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
15config IOSCHED_DEADLINE
16	tristate "Deadline I/O scheduler"
17	default y
18	---help---
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.
23
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
30	  and low latency working environment, suitable for both desktop
31	  and server systems.
32
33	  This is the default I/O scheduler.
34
35config CFQ_GROUP_IOSCHED
36	bool "CFQ Group Scheduling support"
37	depends on IOSCHED_CFQ && BLK_CGROUP
38	default n
39	---help---
40	  Enable group IO scheduling in CFQ.
41
42choice
43
44	prompt "Default I/O scheduler"
45	default DEFAULT_CFQ
46	help
47	  Select the I/O scheduler which will be used by default for all
48	  block devices.
49
50	config DEFAULT_DEADLINE
51		bool "Deadline" if IOSCHED_DEADLINE=y
52
53	config DEFAULT_CFQ
54		bool "CFQ" if IOSCHED_CFQ=y
55
56	config DEFAULT_NOOP
57		bool "No-op"
58
59endchoice
60
61config DEFAULT_IOSCHED
62	string
63	default "deadline" if DEFAULT_DEADLINE
64	default "cfq" if DEFAULT_CFQ
65	default "noop" if DEFAULT_NOOP
66
67config MQ_IOSCHED_DEADLINE
68	tristate "MQ deadline I/O scheduler"
69	default y
70	---help---
71	  MQ version of the deadline IO scheduler.
72
73config MQ_IOSCHED_KYBER
74	tristate "Kyber I/O scheduler"
75	default y
76	---help---
77	  The Kyber I/O scheduler is a low-overhead scheduler suitable for
78	  multiqueue and other fast devices. Given target latencies for reads and
79	  synchronous writes, it will self-tune queue depths to achieve that
80	  goal.
81
82config IOSCHED_BFQ
83	tristate "BFQ I/O scheduler"
84	default n
85	---help---
86	BFQ I/O scheduler for BLK-MQ. BFQ distributes the bandwidth of
87	of the device among all processes according to their weights,
88	regardless of the device parameters and with any workload. It
89	also guarantees a low latency to interactive and soft
90	real-time applications.  Details in
91	Documentation/block/bfq-iosched.txt
92
93config BFQ_GROUP_IOSCHED
94       bool "BFQ hierarchical scheduling support"
95       depends on IOSCHED_BFQ && BLK_CGROUP
96       default n
97       ---help---
98
99       Enable hierarchical scheduling in BFQ, using the blkio
100       (cgroups-v1) or io (cgroups-v2) controller.
101
102endmenu
103
104endif
105