]> git.karo-electronics.de Git - linux-beck.git/commit
sched: Cure load average vs NO_HZ woes
authorPeter Zijlstra <a.p.zijlstra@chello.nl>
Thu, 22 Apr 2010 19:50:19 +0000 (21:50 +0200)
committerIngo Molnar <mingo@elte.hu>
Fri, 23 Apr 2010 09:02:02 +0000 (11:02 +0200)
commit74f5187ac873042f502227701ed1727e7c5fbfa9
treeb200960d04b0a955aaf9a101d6f0a4ed34f07bb2
parent09a40af5240de02d848247ab82440ad75b31ab11
sched: Cure load average vs NO_HZ woes

Chase reported that due to us decrementing calc_load_task prematurely
(before the next LOAD_FREQ sample), the load average could be scewed
by as much as the number of CPUs in the machine.

This patch, based on Chase's patch, cures the problem by keeping the
delta of the CPU going into NO_HZ idle separately and folding that in
on the next LOAD_FREQ update.

This restores the balance and we get strict LOAD_FREQ period samples.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Chase Douglas <chase.douglas@canonical.com>
LKML-Reference: <1271934490.1776.343.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
kernel/sched.c
kernel/sched_idletask.c