From 172b06ad1f781c67c709df994cd3a879e4e83ff0 Mon Sep 17 00:00:00 2001 From: Con Kolivas Date: Wed, 7 Dec 2016 21:23:01 +1100 Subject: [PATCH 13/18] Reinstate default Hz of 100 in combination with MuQSS and -ck patches. --- kernel/Kconfig.hz | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-) Index: linux-4.11-ck1/kernel/Kconfig.hz =================================================================== --- linux-4.11-ck1.orig/kernel/Kconfig.hz 2017-05-12 13:25:56.145572414 +1000 +++ linux-4.11-ck1/kernel/Kconfig.hz 2017-05-12 13:25:56.135572450 +1000 @@ -4,7 +4,8 @@ choice prompt "Timer frequency" - default HZ_250 + default HZ_100_MUQSS if SCHED_MUQSS + default HZ_250 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 @@ -16,15 +17,30 @@ choice per second. + config HZ_100_MUQSS + bool "100 HZ" if SCHED_MUQSS + 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. + config HZ_100 - bool "100 HZ" + bool "100 HZ" if !SCHED_MUQSS help 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_MUQSS + bool "250 HZ" if SCHED_MUQSS + help + 250 Hz is the default choice for the mainline scheduler but not + advantageous in combination with MuQSS. + config HZ_250 - bool "250 HZ" + bool "250 HZ" if !SCHED_MUQSS help 250 Hz is a good compromise choice allowing server performance while also showing good interactive responsiveness even @@ -49,7 +65,9 @@ endchoice config HZ int + default 100 if HZ_100_MUQSS default 100 if HZ_100 + default 250 if HZ_250_MUQSS default 250 if HZ_250 default 300 if HZ_300 default 1000 if HZ_1000