From: Thomas Gleixner Date: Mon, 6 Jun 2011 12:12:51 +0200 Subject: [PATCH 107/290] sched: Limit the number of task migrations per batch Origin: https://git.kernel.org/cgit/linux/kernel/git/rt/linux-stable-rt.git/commit?id=c6286af6b5a433a8f97f2875f2cdcc7fb9614a9d Put an upper limit on the number of tasks which are migrated per batch to avoid large latencies. Signed-off-by: Thomas Gleixner --- kernel/sched/core.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 86839f848805..de93941bad5a 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -44,7 +44,11 @@ const_debug unsigned int sysctl_sched_features = * Number of tasks to iterate in a single balance run. * Limited because this is done with IRQs disabled. */ +#ifdef CONFIG_PREEMPT_RT_FULL +const_debug unsigned int sysctl_sched_nr_migrate = 8; +#else const_debug unsigned int sysctl_sched_nr_migrate = 32; +#endif /* * period over which we measure -rt task CPU usage in us.