Linux Kernel Journey

Aug 5, 2025 · Fundamentals

Why Convert madv_dontneed/madv_free to Per‑VMA Locks in Linux

The article explains how the traditional mmap_lock read lock creates severe contention and priority inversion for frequent madvise MADV_DONTNEED/FREE calls, and how a per‑VMA locking redesign eliminates this bottleneck, improves performance, and is slated for the next Linux kernel release.