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| author | Ingo Molnar <mingo@elte.hu> | 2007-08-24 20:39:10 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2007-08-24 20:39:10 +0200 |
| commit | 71fd37146385c8255bfd370f33ca81fe8c81e5a5 (patch) | |
| tree | 63ef23a5290202c5619d7e3f3f9428d29d5b7db1 /kernel | |
| parent | 7c6c16f354cde4a48bd305b2587fc78257bcb936 (diff) | |
| download | blackbird-op-linux-71fd37146385c8255bfd370f33ca81fe8c81e5a5.tar.gz blackbird-op-linux-71fd37146385c8255bfd370f33ca81fe8c81e5a5.zip | |
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 <mingo@elte.hu>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched.c | 2 | ||||
| -rw-r--r-- | kernel/sched_fair.c | 13 |
2 files changed, 7 insertions, 8 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 96e9b82246d2..e95ff22ed174 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -4923,7 +4923,7 @@ static inline void sched_init_granularity(void) if (sysctl_sched_granularity > gran_limit) sysctl_sched_granularity = gran_limit; - sysctl_sched_runtime_limit = sysctl_sched_granularity * 8; + sysctl_sched_runtime_limit = sysctl_sched_granularity * 5; sysctl_sched_wakeup_granularity = sysctl_sched_granularity / 2; } diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index b5270dc98bef..6b0974c3fb67 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; |
