Tagged articles

select_idle_sibling

3 articles · Page 1 of 1

May 7, 2025 · Fundamentals

Which CPU Does a Woken Task Run On? Understanding wake_affine and select_idle_sibling

The article explains how the Linux kernel decides the CPU for a newly woken task, detailing the roles of wake_affine and select_idle_sibling, the influence of cache topology, run‑queue load, and various idle‑checking heuristics, with concrete examples and code snippets.

CPU affinityLinux kernelrunqueue

0 likes · 9 min read

Which CPU Does a Woken Task Run On? Understanding wake_affine and select_idle_sibling

Linux Code Review Hub

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.

CPU affinitykernelselect_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 2Kernel SchedulingL3 cache

0 likes · 3 min read

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

select_idle_sibling

Which CPU Does a Woken Task Run On? Understanding wake_affine and select_idle_sibling

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