select_idle_sibling — 2 Technical Articles

Mar 30, 2025 · Fundamentals

Where Does a Woken Task Run? Exploring wake_affine and select_idle_sibling in the Linux Scheduler

The article analyzes how the Linux kernel decides the CPU for a task that has just been woken, detailing the roles of wake_affine and select_idle_sibling, and examining factors such as cache affinity, idle status, load, and hardware topology that influence the final placement.

Kernelcpu_affinityselect_idle_sibling

0 likes · 9 min read

Where Does a Woken Task Run? Exploring wake_affine and select_idle_sibling in the Linux Scheduler

Liangxu Linux

Jun 13, 2023 · Fundamentals

How Linux Optimizes AMD Zen 2 CPUs with L3 Cache Enhancements and the select_idle_sibling Patch

Linux will continue supporting AMD Zen 2 processors and improve performance by optimizing L3 cache usage, while the new select_idle_sibling() patch expands idle‑thread selection beyond the local cache, addressing inefficiencies in the kernel’s load‑balancing on multi‑CCD systems.

AMD Zen 2L3 cacheLinux

0 likes · 3 min read

How Linux Optimizes AMD Zen 2 CPUs with L3 Cache Enhancements and the select_idle_sibling Patch

Where Does a Woken Task Run? Exploring wake_affine and select_idle_sibling in the Linux Scheduler

How Linux Optimizes AMD Zen 2 CPUs with L3 Cache Enhancements and the select_idle_sibling Patch

How Linux Optimizes AMD Zen 2 CPUs with L3 Cache Enhancements and the select_idle_sibling Patch