2019-05-19 15:07:45 +03:00
|
|
|
# SPDX-License-Identifier: GPL-2.0-only
|
2005-06-23 11:08:25 +04:00
|
|
|
#
|
|
|
|
|
# Timer Interrupt Frequency Configuration
|
|
|
|
|
#
|
|
|
|
|
|
|
|
|
|
choice
|
|
|
|
|
prompt "Timer frequency"
|
|
|
|
|
default HZ_250
|
|
|
|
|
help
|
|
|
|
|
Allows the configuration of the timer frequency. It is customary
|
2006-12-07 07:37:27 +03:00
|
|
|
to have the timer interrupt run at 1000 Hz but 100 Hz may be more
|
2005-06-23 11:08:25 +04:00
|
|
|
beneficial for servers and NUMA systems that do not need to have
|
|
|
|
|
a fast response for user interaction and that may experience bus
|
|
|
|
|
contention and cacheline bounces as a result of timer interrupts.
|
|
|
|
|
Note that the timer interrupt occurs on each processor in an SMP
|
|
|
|
|
environment leading to NR_CPUS * HZ number of timer interrupts
|
|
|
|
|
per second.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
config HZ_100
|
|
|
|
|
bool "100 HZ"
|
|
|
|
|
help
|
2006-12-07 07:37:27 +03:00
|
|
|
100 Hz is a typical choice for servers, SMP and NUMA systems
|
2005-06-23 11:08:25 +04:00
|
|
|
with lots of processors that may show reduced performance if
|
|
|
|
|
too many timer interrupts are occurring.
|
|
|
|
|
|
|
|
|
|
config HZ_250
|
|
|
|
|
bool "250 HZ"
|
|
|
|
|
help
|
2006-12-07 07:37:27 +03:00
|
|
|
250 Hz is a good compromise choice allowing server performance
|
2005-06-23 11:08:25 +04:00
|
|
|
while also showing good interactive responsiveness even
|
2006-12-07 07:37:27 +03:00
|
|
|
on SMP and NUMA systems. If you are going to be using NTSC video
|
|
|
|
|
or multimedia, selected 300Hz instead.
|
|
|
|
|
|
|
|
|
|
config HZ_300
|
|
|
|
|
bool "300 HZ"
|
|
|
|
|
help
|
|
|
|
|
300 Hz is a good compromise choice allowing server performance
|
|
|
|
|
while also showing good interactive responsiveness even
|
|
|
|
|
on SMP and NUMA systems and exactly dividing by both PAL and
|
|
|
|
|
NTSC frame rates for video and multimedia work.
|
2005-06-23 11:08:25 +04:00
|
|
|
|
|
|
|
|
config HZ_1000
|
|
|
|
|
bool "1000 HZ"
|
|
|
|
|
help
|
2006-12-07 07:37:27 +03:00
|
|
|
1000 Hz is the preferred choice for desktop systems and other
|
2005-06-23 11:08:25 +04:00
|
|
|
systems requiring fast interactive responses to events.
|
|
|
|
|
|
|
|
|
|
endchoice
|
|
|
|
|
|
|
|
|
|
config HZ
|
|
|
|
|
int
|
|
|
|
|
default 100 if HZ_100
|
|
|
|
|
default 250 if HZ_250
|
2006-12-07 07:37:27 +03:00
|
|
|
default 300 if HZ_300
|
2005-06-23 11:08:25 +04:00
|
|
|
default 1000 if HZ_1000
|
|
|
|
|
|
2008-01-25 23:08:29 +03:00
|
|
|
config SCHED_HRTICK
|
2013-11-15 02:32:07 +04:00
|
|
|
def_bool HIGH_RES_TIMERS
|
