From 71fd37146385c8255bfd370f33ca81fe8c81e5a5 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Fri, 24 Aug 2007 20:39:10 +0200 Subject: sched: remove HZ dependency from the granularity default remove HZ dependency from the granularity default. Use 10 msec for the base granularity, 1 msec for wakeup granularity and 25 msec for batch wakeup granularity. (These defaults are close to the values that the default HZ=250 setting got previously, and thus it's the most common setting.) Signed-off-by: Ingo Molnar --- kernel/sched_fair.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) (limited to 'kernel/sched_fair.c') diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index b5270dc98be..6b0974c3fb6 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -19,7 +19,7 @@ /* * Preemption granularity: - * (default: 2 msec, units: nanoseconds) + * (default: 10 msec, units: nanoseconds) * * NOTE: this granularity value is not the same as the concept of * 'timeslice length' - timeslices in CFS will typically be somewhat @@ -31,18 +31,17 @@ * number of CPUs. (i.e. factor 2x on 2-way systems, 3x on 4-way * systems, 4x on 8-way systems, 5x on 16-way systems, etc.) */ -unsigned int sysctl_sched_granularity __read_mostly = 2000000000ULL/HZ; +unsigned int sysctl_sched_granularity __read_mostly = 10000000UL; /* * SCHED_BATCH wake-up granularity. - * (default: 10 msec, units: nanoseconds) + * (default: 25 msec, units: nanoseconds) * * This option delays the preemption effects of decoupled workloads * and reduces their over-scheduling. Synchronous workloads will still * have immediate wakeup/sleep latencies. */ -unsigned int sysctl_sched_batch_wakeup_granularity __read_mostly = - 10000000000ULL/HZ; +unsigned int sysctl_sched_batch_wakeup_granularity __read_mostly = 25000000UL; /* * SCHED_OTHER wake-up granularity. @@ -52,12 +51,12 @@ unsigned int sysctl_sched_batch_wakeup_granularity __read_mostly = * and reduces their over-scheduling. Synchronous workloads will still * have immediate wakeup/sleep latencies. */ -unsigned int sysctl_sched_wakeup_granularity __read_mostly = 1000000000ULL/HZ; +unsigned int sysctl_sched_wakeup_granularity __read_mostly = 1000000UL; unsigned int sysctl_sched_stat_granularity __read_mostly; /* - * Initialized in sched_init_granularity(): + * Initialized in sched_init_granularity() [to 5 times the base granularity]: */ unsigned int sysctl_sched_runtime_limit __read_mostly; -- cgit v1.2.3-70-g09d2