The scheduler updates have been merged for the in-development Linux 7.4 kernel to deliver several nice scheduling enhancements.
First up is a EEVDF scheduler update for improving the scheduling latency of short-slice tasks. Linaro engineer Vincent Guittot worked on the latest scheduling latency improvements around short slice tasks. Overall some very nice improvements up to 55% lower latency observed with these patches for Linux 7.4:
This is in addition to short slice task scheduler improvements Vincent also made in the Linux 7.3 kernel.
New to the scheduling area with Linux 7.4 is the steal governor for enhancing Linux VMs. The steal governor is for dynamic vCPU management based on steal time for reducing vCPU preemption costs.
Another notable scheduler change is the NVIDIA Olympus core enhancement for Vera CPUs to prefer SMT siblings for better performance. See more details in NVIDIA Olympus SMT Optimizations For Vera CPU Showing 3~6% Performance Gains.
The scheduler pull also contains the work for randomly picking idle CPU cores among equally-shallow CPU cores for better performance, namely on high core count servers/workstations.
On the cache aware scheduling side, there is a fix to avoid publishing partial last level cache (LLC) utilization data.
More details on the many scheduler improvements merged for Linux 7.4 can be found via this pull request.