Earliest eligible virtual deadline first (EEVDF) is a dynamic priority proportional share scheduling algorithm for soft real-time systems.

Algorithm

EEVDF was first described in the 1995 paper "Earliest Eligible Virtual Deadline First : A Flexible and Accurate Mechanism for Proportional Share Resource Allocation" by Ion Stoica and Hussein Abdel-Wahab. It uses notions of virtual time, eligible time, virtual requests and virtual deadlines for determining scheduling priority. It has the property that when a job keeps requesting service, the amount of service obtained is always within the maximum quantum size of what it is entitled.

Linux kernel scheduler

In 2023, Peter Zijlstra proposed replacing the

Completely Fair Scheduler The Completely Fair Scheduler (CFS) was a process scheduler that was merged into the 2.6.23 (October 2007) release of the Linux Linux kernel, kernel. It was the default scheduler of the tasks of the SCHED_NORMAL class (i.e., tasks that have no re ...

(CFS) in the

Linux kernel The Linux kernel is a Free and open-source software, free and open source Unix-like kernel (operating system), kernel that is used in many computer systems worldwide. The kernel was created by Linus Torvalds in 1991 and was soon adopted as the k ...

with an EEVDF process scheduler. The aim was to remove the need for CFS "latency nice" patches. The EEVDF scheduler replaced CFS in version 6.6 of the Linux kernel.

References

{{Linux kernel Processor scheduling algorithms Real-time computing Linux kernel process schedulers

Algorithm

Linux kernel scheduler

See also

References