#scheduler #userspace #fifo #bpf

app scx_rlfifo

A simple FIFO scheduler in Rust that runs in user-space

1 unstable release

0.0.3 Jun 3, 2024

#136 in Unix APIs

Download history 73/week @ 2024-05-28 107/week @ 2024-06-04 7/week @ 2024-06-11

187 downloads per month


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This is a single user-defined scheduler used within sched_ext, which is a Linux kernel feature which enables implementing kernel thread schedulers in BPF and dynamically loading them. Read more about sched_ext.


scx_rlfifo is a simple FIFO scheduler runs in user-space, based on the scx_rustland_core framework.

Typical Use Case

This scheduler is provided as a simple template that can be used as a baseline to test more complex scheduling policies.

Production Ready?

Definitely not. Using this scheduler in a production environment is not recommended, unless there are specific requirements that necessitate a basic FIFO scheduling approach. Even then, it's still recommended to use the kernel's SCHED_FIFO real-time class.


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