Kconfig.hz 1.6 KB

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  1. #
  2. # Timer Interrupt Frequency Configuration
  3. #
  4. choice
  5. prompt "Timer frequency"
  6. default HZ_250
  7. help
  8. Allows the configuration of the timer frequency. It is customary
  9. to have the timer interrupt run at 1000 Hz but 100 Hz may be more
  10. beneficial for servers and NUMA systems that do not need to have
  11. a fast response for user interaction and that may experience bus
  12. contention and cacheline bounces as a result of timer interrupts.
  13. Note that the timer interrupt occurs on each processor in an SMP
  14. environment leading to NR_CPUS * HZ number of timer interrupts
  15. per second.
  16. config HZ_100
  17. bool "100 HZ"
  18. help
  19. 100 Hz is a typical choice for servers, SMP and NUMA systems
  20. with lots of processors that may show reduced performance if
  21. too many timer interrupts are occurring.
  22. config HZ_250
  23. bool "250 HZ"
  24. help
  25. 250 Hz is a good compromise choice allowing server performance
  26. while also showing good interactive responsiveness even
  27. on SMP and NUMA systems. If you are going to be using NTSC video
  28. or multimedia, selected 300Hz instead.
  29. config HZ_300
  30. bool "300 HZ"
  31. help
  32. 300 Hz is a good compromise choice allowing server performance
  33. while also showing good interactive responsiveness even
  34. on SMP and NUMA systems and exactly dividing by both PAL and
  35. NTSC frame rates for video and multimedia work.
  36. config HZ_1000
  37. bool "1000 HZ"
  38. help
  39. 1000 Hz is the preferred choice for desktop systems and other
  40. systems requiring fast interactive responses to events.
  41. endchoice
  42. config HZ
  43. int
  44. default 100 if HZ_100
  45. default 250 if HZ_250
  46. default 300 if HZ_300
  47. default 1000 if HZ_1000
  48. config SCHED_HRTICK
  49. def_bool HIGH_RES_TIMERS