block/Kconfig.iosched

   1 # SPDX-License-Identifier: GPL-2.0
   2 if BLOCK
   3
   4 menu "IO Schedulers"
   5
   6 config 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
  16 config 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
  25 config 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
  36 config 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
  42 choice
  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
  59 endchoice
  60
  61 config DEFAULT_IOSCHED
  62         string
  63         default "deadline" if DEFAULT_DEADLINE
  64         default "cfq" if DEFAULT_CFQ
  65         default "noop" if DEFAULT_NOOP
  66
  67 config MQ_IOSCHED_DEADLINE
  68         tristate "MQ deadline I/O scheduler"
  69         default y
  70         ---help---
  71           MQ version of the deadline IO scheduler.
  72
  73 config 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
  82 config 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
  92 config 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
 100 endmenu
 101
 102 endif