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author | Ingo Molnar <mingo@elte.hu> | 2007-11-09 22:39:38 +0100 |
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committer | Ingo Molnar <mingo@elte.hu> | 2007-11-09 22:39:38 +0100 |
commit | 19978ca610946ed57c071bad63f8f6642ca1298b (patch) | |
tree | 3bdbe89a249b6091fbd71653f106f486337ca3d6 /kernel/sched_fair.c | |
parent | fa13a5a1f25f671d084d8884be96fc48d9b68275 (diff) | |
download | lwn-19978ca610946ed57c071bad63f8f6642ca1298b.tar.gz lwn-19978ca610946ed57c071bad63f8f6642ca1298b.zip |
sched: reintroduce SMP tunings again
Yanmin Zhang reported an aim7 regression and bisected it down to:
| commit 38ad464d410dadceda1563f36bdb0be7fe4c8938
| Author: Ingo Molnar <mingo@elte.hu>
| Date: Mon Oct 15 17:00:02 2007 +0200
|
| sched: uniform tunings
|
| use the same defaults on both UP and SMP.
fix this by reintroducing similar SMP tunings again. This resolves
the regression.
(also update the comments to match the ilog2(nr_cpus) tuning effect)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched_fair.c')
-rw-r--r-- | kernel/sched_fair.c | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index c495dcf7031b..7264814ba62a 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -22,7 +22,7 @@ /* * Targeted preemption latency for CPU-bound tasks: - * (default: 20ms, units: nanoseconds) + * (default: 20ms * ilog(ncpus), units: nanoseconds) * * NOTE: this latency value is not the same as the concept of * 'timeslice length' - timeslices in CFS are of variable length @@ -32,18 +32,18 @@ * (to see the precise effective timeslice length of your workload, * run vmstat and monitor the context-switches (cs) field) */ -const_debug unsigned int sysctl_sched_latency = 20000000ULL; +unsigned int sysctl_sched_latency = 20000000ULL; /* * Minimal preemption granularity for CPU-bound tasks: - * (default: 1 msec, units: nanoseconds) + * (default: 1 msec * ilog(ncpus), units: nanoseconds) */ -const_debug unsigned int sysctl_sched_min_granularity = 1000000ULL; +unsigned int sysctl_sched_min_granularity = 1000000ULL; /* * is kept at sysctl_sched_latency / sysctl_sched_min_granularity */ -const_debug unsigned int sched_nr_latency = 20; +unsigned int sched_nr_latency = 20; /* * After fork, child runs first. (default) If set to 0 then @@ -61,23 +61,23 @@ unsigned int __read_mostly sysctl_sched_compat_yield; /* * SCHED_BATCH wake-up granularity. - * (default: 10 msec, units: nanoseconds) + * (default: 10 msec * ilog(ncpus), 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. */ -const_debug unsigned int sysctl_sched_batch_wakeup_granularity = 10000000UL; +unsigned int sysctl_sched_batch_wakeup_granularity = 10000000UL; /* * SCHED_OTHER wake-up granularity. - * (default: 10 msec, units: nanoseconds) + * (default: 10 msec * ilog(ncpus), 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. */ -const_debug unsigned int sysctl_sched_wakeup_granularity = 10000000UL; +unsigned int sysctl_sched_wakeup_granularity = 10000000UL; const_debug unsigned int sysctl_sched_migration_cost = 500000UL; |