scheduler
Module
Module Summary
Since
Description
This module contains utility functions for easier measurement and calculation of scheduler utilization, otherwise obtained from calling the more primitive statistics(scheduler_wall_time).
The simplest usage is to call scheduler:utilization(Seconds).
Data Types
[{sched_type(), sched_id(), float(), string()} |
{total, float(), string()} |
{weighted, float(), string()}]
A list of tuples containing results for individual schedulers as well as aggregated averages. Util is the scheduler utilization as a floating point value between 0.0 and 1.0. Percent is the same utilization as a more human readable string expressed in percent.
- {normal, SchedulerId, Util, Percent}
- Scheduler utilization of a normal scheduler with number SchedulerId.
- {cpu, SchedulerId, Util, Percent}
- Scheduler utilization of a dirty-cpu scheduler with number SchedulerId.
- {io, SchedulerId, Util, Percent}
- Scheduler utilization of a dirty-io scheduler with number SchedulerId. This tuple will only exist if both samples were taken with sample_all/0.
- {total, Util, Percent}
- Total utilization of all normal and dirty-cpu schedulers.
- {weighted, Util, Percent}
- Total utilization of all normal and dirty-cpu schedulers, weighted against maximum amount of available CPU time.
Exports
sample() -> sched_sample()
|
OTP 21.0 |
Return a scheduler utilization sample for normal and dirty-cpu schedulers.
sample_all() -> sched_sample()
|
OTP 21.0 |
Return a scheduler utilization sample for all schedulers, including dirty-io schedulers.
utilization(Seconds) -> sched_util_result()
|
OTP 21.0 |
Types
Measure utilization for normal and dirty-cpu schedulers during Seconds seconds, and then return the result.
utilization(Sample) -> sched_util_result()
|
OTP 21.0 |
Types
Calculate scheduler utilizations for the time interval from when Sample was taken and "now". The same as calling scheduler:utilization(Sample, scheduler:sample_all()).
utilization(Sample1, Sample2) -> sched_util_result()
|
OTP 21.0 |
Calculates scheduler utilizations for the time interval between the two samples obtained from calling sample/0 or sample_all/0.