Linux Kernel Journey

Feb 16, 2025 · Fundamentals

Understanding Multi‑Core Hardware Topology and Linux sched_domain

The article explains how Linux kernel scheduling uses a hierarchical topology—balancing load and preserving cache affinity—by mapping real‑world multi‑core hardware structures such as sockets, dies, clusters, and NUMA nodes to sched_domain and sched_group, and shows how to inspect and tune this layout with CONFIG_SCHED_DEBUG and QEMU simulation.