Linux Scheduler Comparison

This work compares the performance and power consumption of 7 different scheduling policies including two real-time policies with 5 benchmark utilities.

Scheduling Policies

• SCHED_IDLE
• SCHED_OTHER and nice=20
• SCHED_OTHER and nice=-19
• SCHED_FIFO and prio=49
• SCHED_RR and prio=49
• SCHED_RT_FIFO* and prio=49
• SCHED_RT_RR* and prio=49

_{* SCHED_RT_X policy is the policy SCHED_X used in real-time kernel}

Benchmarks

Benchmark	Introduction
Latt	Simple latency tester that combines multiple processes
Hackbench	Scheduler stress tester by creating pairs of entities communicate via either sockets or pipes
FFmpeg	Test the systemss audio/video encoding performance
7-Zip Compression	A built-in LZMA benchmark
John The Ripper	A password cracker and performance measured in c/s

Results

Current Change Example (FFmpeg)

Click here to view more figures.

Full benchmark result scheduler-comparison on OpenBenchmarking.org

The paper for this project.

References

• Molnar, Ingo. "CFS scheduler." Linux. Vol. 2. 2007.
• Jones, M. Tim. "Inside the linux 2.6 completely fair scheduler." IBM Developer Works Technical Report 2009 (2009).
• sched - overview of CPU scheduling