diff options
Diffstat (limited to 'kernel/sched')
| -rw-r--r-- | kernel/sched/fair.c | 50 |
1 files changed, 28 insertions, 22 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 02605f2826a2..aa475896782d 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -37,7 +37,6 @@ /* * Targeted preemption latency for CPU-bound tasks: - * (default: 6ms * (1 + 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 @@ -46,31 +45,35 @@ * * (to see the precise effective timeslice length of your workload, * run vmstat and monitor the context-switches (cs) field) + * + * (default: 6ms * (1 + ilog(ncpus)), units: nanoseconds) */ -unsigned int sysctl_sched_latency = 6000000ULL; -unsigned int normalized_sysctl_sched_latency = 6000000ULL; +unsigned int sysctl_sched_latency = 6000000ULL; +unsigned int normalized_sysctl_sched_latency = 6000000ULL; /* * The initial- and re-scaling of tunables is configurable - * (default SCHED_TUNABLESCALING_LOG = *(1+ilog(ncpus)) * * Options are: - * SCHED_TUNABLESCALING_NONE - unscaled, always *1 - * SCHED_TUNABLESCALING_LOG - scaled logarithmical, *1+ilog(ncpus) - * SCHED_TUNABLESCALING_LINEAR - scaled linear, *ncpus + * + * SCHED_TUNABLESCALING_NONE - unscaled, always *1 + * SCHED_TUNABLESCALING_LOG - scaled logarithmical, *1+ilog(ncpus) + * SCHED_TUNABLESCALING_LINEAR - scaled linear, *ncpus + * + * (default SCHED_TUNABLESCALING_LOG = *(1+ilog(ncpus)) */ -enum sched_tunable_scaling sysctl_sched_tunable_scaling - = SCHED_TUNABLESCALING_LOG; +enum sched_tunable_scaling sysctl_sched_tunable_scaling = SCHED_TUNABLESCALING_LOG; /* * Minimal preemption granularity for CPU-bound tasks: + * * (default: 0.75 msec * (1 + ilog(ncpus)), units: nanoseconds) */ -unsigned int sysctl_sched_min_granularity = 750000ULL; -unsigned int normalized_sysctl_sched_min_granularity = 750000ULL; +unsigned int sysctl_sched_min_granularity = 750000ULL; +unsigned int normalized_sysctl_sched_min_granularity = 750000ULL; /* - * is kept at sysctl_sched_latency / sysctl_sched_min_granularity + * This value is kept at sysctl_sched_latency/sysctl_sched_min_granularity */ static unsigned int sched_nr_latency = 8; @@ -82,16 +85,17 @@ unsigned int sysctl_sched_child_runs_first __read_mostly; /* * SCHED_OTHER wake-up granularity. - * (default: 1 msec * (1 + 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. + * + * (default: 1 msec * (1 + ilog(ncpus)), units: nanoseconds) */ -unsigned int sysctl_sched_wakeup_granularity = 1000000UL; -unsigned int normalized_sysctl_sched_wakeup_granularity = 1000000UL; +unsigned int sysctl_sched_wakeup_granularity = 1000000UL; +unsigned int normalized_sysctl_sched_wakeup_granularity = 1000000UL; -const_debug unsigned int sysctl_sched_migration_cost = 500000UL; +const_debug unsigned int sysctl_sched_migration_cost = 500000UL; #ifdef CONFIG_CFS_BANDWIDTH /* @@ -102,16 +106,18 @@ const_debug unsigned int sysctl_sched_migration_cost = 500000UL; * to consumption or the quota being specified to be smaller than the slice) * we will always only issue the remaining available time. * - * default: 5 msec, units: microseconds - */ -unsigned int sysctl_sched_cfs_bandwidth_slice = 5000UL; + * (default: 5 msec, units: microseconds) + */ +unsigned int sysctl_sched_cfs_bandwidth_slice = 5000UL; #endif /* * The margin used when comparing utilization with CPU capacity: * util * margin < capacity * 1024 + * + * (default: ~20%) */ -unsigned int capacity_margin = 1280; /* ~20% */ +unsigned int capacity_margin = 1280; static inline void update_load_add(struct load_weight *lw, unsigned long inc) { @@ -7174,8 +7180,8 @@ check_cpu_capacity(struct rq *rq, struct sched_domain *sd) * cpumask covering 1 cpu of the first group and 3 cpus of the second group. * Something like: * - * { 0 1 2 3 } { 4 5 6 7 } - * * * * * + * { 0 1 2 3 } { 4 5 6 7 } + * * * * * * * If we were to balance group-wise we'd place two tasks in the first group and * two tasks in the second group. Clearly this is undesired as it will overload |