1# SPDX-License-Identifier: GPL-2.0 2if BLOCK 3 4menu "IO Schedulers" 5 6config IOSCHED_NOOP 7 bool 8 default y 9 ---help--- 10 The no-op I/O scheduler is a minimal scheduler that does basic merging 11 and sorting. Its main uses include non-disk based block devices like 12 memory devices, and specialised software or hardware environments 13 that do their own scheduling and require only minimal assistance from 14 the kernel. 15 16config IOSCHED_DEADLINE 17 tristate "Deadline I/O scheduler" 18 default y 19 ---help--- 20 The deadline I/O scheduler is simple and compact. It will provide 21 CSCAN service with FIFO expiration of requests, switching to 22 a new point in the service tree and doing a batch of IO from there 23 in case of expiry. 24 25config IOSCHED_CFQ 26 tristate "CFQ I/O scheduler" 27 default y 28 ---help--- 29 The CFQ I/O scheduler tries to distribute bandwidth equally 30 among all processes in the system. It should provide a fair 31 and low latency working environment, suitable for both desktop 32 and server systems. 33 34 This is the default I/O scheduler. 35 36config CFQ_GROUP_IOSCHED 37 bool "CFQ Group Scheduling support" 38 depends on IOSCHED_CFQ && BLK_CGROUP 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 ---help--- 85 BFQ I/O scheduler for BLK-MQ. BFQ distributes the bandwidth of 86 of the device among all processes according to their weights, 87 regardless of the device parameters and with any workload. It 88 also guarantees a low latency to interactive and soft 89 real-time applications. Details in 90 Documentation/block/bfq-iosched.txt 91 92config BFQ_GROUP_IOSCHED 93 bool "BFQ hierarchical scheduling support" 94 depends on IOSCHED_BFQ && BLK_CGROUP 95 ---help--- 96 97 Enable hierarchical scheduling in BFQ, using the blkio 98 (cgroups-v1) or io (cgroups-v2) controller. 99 100endmenu 101 102endif 103