linux/block/Kconfig.iosched
<<
>>
Prefs
   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        prompt "Default I/O scheduler"
  44        default DEFAULT_CFQ
  45        help
  46          Select the I/O scheduler which will be used by default for all
  47          block devices.
  48
  49        config DEFAULT_DEADLINE
  50                bool "Deadline" if IOSCHED_DEADLINE=y
  51
  52        config DEFAULT_CFQ
  53                bool "CFQ" if IOSCHED_CFQ=y
  54
  55        config DEFAULT_NOOP
  56                bool "No-op"
  57
  58endchoice
  59
  60config DEFAULT_IOSCHED
  61        string
  62        default "deadline" if DEFAULT_DEADLINE
  63        default "cfq" if DEFAULT_CFQ
  64        default "noop" if DEFAULT_NOOP
  65
  66endmenu
  67
  68endif
  69