System information

174 System Analysis and Tuning Guide
This value also specifies the maximum amount of time during which a sleeping
task is considered to be running for entitlement calculations. Increasing this vari-
able increases the amount of time a waking task may consume before being pre-
empted, thus increasing scheduler latency for CPU bound tasks. The default value
is 20000000 (ns).
sched_min_granularity_ns
Minimal preemption granularity for CPU bound tasks. See
sched_latency_ns for details. The default value is 4000000 (ns).
sched_wakeup_granularity_ns
The wake-up preemption granularity. Increasing this variable reduces wake-up
preemption, reducing disturbance of compute bound tasks. Lowering it improves
wake-up latency and throughput for latency critical tasks, particularly when a
short duty cycle load component must compete with CPU bound components.
The default value is 5000000 (ns).
WARNING
Settings larger than half of sched_latency_ns will result in zero wake-
up preemption and short duty cycle tasks will be unable to compete with
CPU hogs effectively.
sched_rt_period_us
Period over which real-time task bandwidth enforcement is measured. The de-
fault value is 1000000 (µs).
sched_rt_runtime_us
Quantum allocated to real-time tasks during sched_rt_period_us. Setting to -1 dis-
ables RT bandwidth enforcement. By default, RT tasks may consume 95%CPU/
sec, thus leaving 5%CPU/sec or 0.05s to be used by SCHED_OTHER tasks.
sched_features
Provides information about specific debugging features.
sched_stat_granularity_ns
Specifies the granularity for collecting task scheduler statistics.
sched_nr_migrate
Controls how many tasks can be moved across processors through migra-
tion software interrupts (softirq). If a large number of tasks is created by