Updated EEVDF Linux CPU Scheduler Patches Posted That Plan To Replace CFS

Intel engineer Peter Zijlstra on Wednesday posted the latest patches for the EEVDF scheduler, the Earliest Eligible Virtual Deadline First approach that is based on a research paper from the late 90's. Ultimately the hope is for EEVDF to replace the existing CFS scheduler code.

With the new patch series there is a fix for tick-preemption and a simple safe-guard added but otherwise is largely similar to prior Linux EEVDF patches. The performance shouldn't be different out of these revised patches and what it should show is providing better latency and smaller variance compared to the existing CFS scheduler code.

The research paper from 1996 on which the Linux EEVDF scheduler patches are based.

With the lower latency and EEVDF looking favorable, Zijlstra is "hoping we can start queuing this part" for getting the new scheduler code upstream. There is though some open items for the kernel developers to discuss around the exposed interfaces.

See the patch series if wanting to learn more about the EEVDF scheduler. As part of the patch series is committing to EEVDF by gutting CFS. Peter wrote on that patch deleting 450 lines of CFS code, "EEVDF is a better defined scheduling policy, as a result it has less heuristics/tunables. There is no compelling reason to keep CFS around."

So here's to hoping we begin to see the EEVDF scheduler patches landing soon in the mainline Linux kernel.