1# SPDX-License-Identifier: GPL-2.0-only 2# 3# Timer Interrupt Frequency Configuration 4# 5 6choice 7 prompt "Timer frequency" 8 default HZ_250 9 help 10 Allows the configuration of the timer frequency. It is customary 11 to have the timer interrupt run at 1000 Hz but 100 Hz may be more 12 beneficial for servers and NUMA systems that do not need to have 13 a fast response for user interaction and that may experience bus 14 contention and cacheline bounces as a result of timer interrupts. 15 Note that the timer interrupt occurs on each processor in an SMP 16 environment leading to NR_CPUS * HZ number of timer interrupts 17 per second. 18 19 20 config HZ_100 21 bool "100 HZ" 22 help 23 100 Hz is a typical choice for servers, SMP and NUMA systems 24 with lots of processors that may show reduced performance if 25 too many timer interrupts are occurring. 26 27 config HZ_250 28 bool "250 HZ" 29 help 30 250 Hz is a good compromise choice allowing server performance 31 while also showing good interactive responsiveness even 32 on SMP and NUMA systems. If you are going to be using NTSC video 33 or multimedia, selected 300Hz instead. 34 35 config HZ_300 36 bool "300 HZ" 37 help 38 300 Hz is a good compromise choice allowing server performance 39 while also showing good interactive responsiveness even 40 on SMP and NUMA systems and exactly dividing by both PAL and 41 NTSC frame rates for video and multimedia work. 42 43 config HZ_1000 44 bool "1000 HZ" 45 help 46 1000 Hz is the preferred choice for desktop systems and other 47 systems requiring fast interactive responses to events. 48 49endchoice 50 51config HZ 52 int 53 default 100 if HZ_100 54 default 250 if HZ_250 55 default 300 if HZ_300 56 default 1000 if HZ_1000 57 58config SCHED_HRTICK 59 def_bool HIGH_RES_TIMERS 60