diff options
| author | Con Kolivas <kernel@kolivas.org> | 2016-12-07 21:23:01 +1100 |
|---|---|---|
| committer | Con Kolivas <kernel@kolivas.org> | 2019-05-15 16:11:15 +1000 |
| commit | f1b776971e6aa46347f035adfebfd71d5f0930bb (patch) | |
| tree | e3e07b29c8663090c2eed6434415728a7df0d86c | |
| parent | 50ddde6e3c62abd39dc6a3cd5941febed7ad49c3 (diff) | |
Reinstate default Hz of 100 in combination with MuQSS and -ck patches.
| -rw-r--r-- | kernel/Kconfig.hz | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/kernel/Kconfig.hz b/kernel/Kconfig.hz index 2a202a846757..1806fcac8f14 100644 --- a/kernel/Kconfig.hz +++ b/kernel/Kconfig.hz @@ -4,7 +4,8 @@ choice prompt "Timer frequency" - default HZ_250 + default HZ_100 if SCHED_MUQSS + default HZ_250_NODEF if !SCHED_MUQSS help Allows the configuration of the timer frequency. It is customary to have the timer interrupt run at 1000 Hz but 100 Hz may be more @@ -19,11 +20,18 @@ choice config HZ_100 bool "100 HZ" help + 100 Hz is a suitable choice in combination with MuQSS which does + not rely on ticks for rescheduling interrupts, and is not Hz limited + for timeouts and sleeps from both the kernel and userspace. + This allows us to benefit from the lower overhead and higher + throughput of fewer timer ticks. + + Non-MuQSS kernels: 100 Hz is a typical choice for servers, SMP and NUMA systems with lots of processors that may show reduced performance if too many timer interrupts are occurring. - config HZ_250 + config HZ_250_NODEF bool "250 HZ" help 250 Hz is a good compromise choice allowing server performance @@ -31,7 +39,10 @@ choice on SMP and NUMA systems. If you are going to be using NTSC video or multimedia, selected 300Hz instead. - config HZ_300 + 250 Hz is the default choice for the mainline scheduler but not + advantageous in combination with MuQSS. + + config HZ_300_NODEF bool "300 HZ" help 300 Hz is a good compromise choice allowing server performance @@ -39,7 +50,7 @@ choice on SMP and NUMA systems and exactly dividing by both PAL and NTSC frame rates for video and multimedia work. - config HZ_1000 + config HZ_1000_NODEF bool "1000 HZ" help 1000 Hz is the preferred choice for desktop systems and other @@ -50,9 +61,9 @@ endchoice config HZ int default 100 if HZ_100 - default 250 if HZ_250 - default 300 if HZ_300 - default 1000 if HZ_1000 + default 250 if HZ_250_NODEF + default 300 if HZ_300_NODEF + default 1000 if HZ_1000_NODEF config SCHED_HRTICK def_bool HIGH_RES_TIMERS |