Kconfig.iosched 1.8 KB

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  1. if BLOCK
  2. menu "IO Schedulers"
  3. config IOSCHED_NOOP
  4. bool
  5. default y
  6. ---help---
  7. The no-op I/O scheduler is a minimal scheduler that does basic merging
  8. and sorting. Its main uses include non-disk based block devices like
  9. memory devices, and specialised software or hardware environments
  10. that do their own scheduling and require only minimal assistance from
  11. the kernel.
  12. config IOSCHED_DEADLINE
  13. tristate "Deadline I/O scheduler"
  14. default y
  15. ---help---
  16. The deadline I/O scheduler is simple and compact. It will provide
  17. CSCAN service with FIFO expiration of requests, switching to
  18. a new point in the service tree and doing a batch of IO from there
  19. in case of expiry.
  20. config IOSCHED_CFQ
  21. tristate "CFQ I/O scheduler"
  22. default y
  23. ---help---
  24. The CFQ I/O scheduler tries to distribute bandwidth equally
  25. among all processes in the system. It should provide a fair
  26. and low latency working environment, suitable for both desktop
  27. and server systems.
  28. This is the default I/O scheduler.
  29. config CFQ_GROUP_IOSCHED
  30. bool "CFQ Group Scheduling support"
  31. depends on IOSCHED_CFQ && CGROUPS
  32. select BLK_CGROUP
  33. default n
  34. ---help---
  35. Enable group IO scheduling in CFQ.
  36. config DEBUG_CFQ_IOSCHED
  37. bool "Debug CFQ Scheduling"
  38. depends on CFQ_GROUP_IOSCHED
  39. select DEBUG_BLK_CGROUP
  40. default n
  41. ---help---
  42. Enable CFQ IO scheduling debugging in CFQ. Currently it makes
  43. blktrace output more verbose.
  44. choice
  45. prompt "Default I/O scheduler"
  46. default DEFAULT_CFQ
  47. help
  48. Select the I/O scheduler which will be used by default for all
  49. block devices.
  50. config DEFAULT_DEADLINE
  51. bool "Deadline" if IOSCHED_DEADLINE=y
  52. config DEFAULT_CFQ
  53. bool "CFQ" if IOSCHED_CFQ=y
  54. config DEFAULT_NOOP
  55. bool "No-op"
  56. endchoice
  57. config DEFAULT_IOSCHED
  58. string
  59. default "deadline" if DEFAULT_DEADLINE
  60. default "cfq" if DEFAULT_CFQ
  61. default "noop" if DEFAULT_NOOP
  62. endmenu
  63. endif