scx/scheds/rust/scx_lavd
Tejun Heo 1bba713a29
Merge pull request #542 from sched-ext/htejun/scx_stats
scx_stats, scx_rusty, scx_layered: Implement `--help-stats`
2024-08-24 15:38:36 -10:00
..
src scx_lavd: Fix my own formatting error 2024-08-24 11:36:19 -04:00
.gitignore scheds/rust: Include Cargo.lock in the repo 2024-08-15 23:08:35 -10:00
build.rs scx_lavd: add scx_lavd (Latency-criticality Aware Virtual Deadline) scheduler 2024-03-16 10:31:07 +09:00
Cargo.lock scx_lavd: Cargo.lock update (caused by scx_utils depending on scx_stats) 2024-08-23 09:21:44 -10:00
Cargo.toml Version: v1.0.3 2024-08-21 06:42:11 -10:00
LICENSE scx_lavd: add scx_lavd (Latency-criticality Aware Virtual Deadline) scheduler 2024-03-16 10:31:07 +09:00
meson.build meson: introduce serialize build option 2024-06-28 10:17:37 +02:00
README.md scx_lavd: add scx_lavd (Latency-criticality Aware Virtual Deadline) scheduler 2024-03-16 10:31:07 +09:00
rustfmt.toml scx_lavd: add scx_lavd (Latency-criticality Aware Virtual Deadline) scheduler 2024-03-16 10:31:07 +09:00

scx_lavd

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.

Overview

scx_lavd is a BPF scheduler that implements an LAVD (Latency-criticality Aware Virtual Deadline) scheduling algorithm. While LAVD is new and still evolving, its core ideas are 1) measuring how much a task is latency critical and 2) leveraging the task's latency-criticality information in making various scheduling decisions (e.g., task's deadline, time slice, etc.). As the name implies, LAVD is based on the foundation of deadline scheduling. This scheduler consists of the BPF part and the rust part. The BPF part makes all the scheduling decisions; the rust part loads the BPF code and conducts other chores (e.g., printing sampled scheduling decisions).

Typical Use Case

scx_lavd is initially motivated by gaming workloads. It aims to improve interactivity and reduce stuttering while playing games on Linux. Hence, this scheduler's typical use case involves highly interactive applications, such as gaming, which requires high throughput and low tail latencies.

Production Ready?

This scheduler could be used in a production environment where the current code is optimized. The current code does not particularly consider multiple NUMA/CCX domains, so its scheduling decisions in such hardware would be suboptimal. This scheduler currently will mainly perform well on single CCX / single-socket hosts.