From 19978ca610946ed57c071bad63f8f6642ca1298b Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Fri, 9 Nov 2007 22:39:38 +0100 Subject: sched: reintroduce SMP tunings again Yanmin Zhang reported an aim7 regression and bisected it down to: | commit 38ad464d410dadceda1563f36bdb0be7fe4c8938 | Author: Ingo Molnar | 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 --- kernel/sched_fair.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) (limited to 'kernel/sched_fair.c') diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index c495dcf7031..7264814ba62 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; -- cgit v1.2.3