Linux 5.4 Scheduler Changes Bring Better AMD EPYC Load Balancing, Other Optimizations

Written by Michael Larabel in Linux Kernel on 16 September 2019 at 05:49 PM EDT. Add A Comment
The Linux 5.4 scheduler changes are fairly exciting on multiple fronts.

One of the Linux 5.4 scheduler changes we have been looking forward to is improved EPYC load balancing and that work is indeed part of today's pull request. The better EPYC load balancing is a scheduler topology improvement to better deal with load balancing across NUMA nodes on EPYC 2P servers. I'll be running some benchmarks of this EPYC-specific scheduler change in the days ahead.

Beyond that, there are a number of other EPYC improvements coming for Linux 5.4:

- Improved balancing when SCHED_IDLE tasks are present.

- More patches bringing the real-time PREEMPT_RT tree closer to the mainline code, but a few hundred patches are still out-of-tree.

- The CPU cgroup controller now supports min and max tunables for better CPU bandwidth usage handling.

- Improvements of high CPU core counts with high thread count applications being limited by cpu.cfs_quota_us.

- Various other improvements.

More details via the scheduler pull request for Linux 5.4.
Related News
About The Author
Michael Larabel

Michael Larabel is the principal author of and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 20,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and automated benchmarking software. He can be followed via Twitter, LinkedIn, or contacted via

Popular News This Week