• [$] Keeping COWs in context (a.k.a. anonymous reverse mapping)

    From LWN.net@618:250/24 to All on Fri May 15 06:40:08 2026
    The kernel's reverse-mapping machinery is charged with locating the
    page-table entries that refer to a given page in memory. The reverse
    mapping of anonymous pages is handled differently than for file-backed
    pages. The kernel's implementation of reverse mapping for anonymous pages
    is, according to Lorenzo Stoakes in his proposal
    for a memory-management-track session at the 2026 Linux Storage,
    Filesystem, Memory Management, and BPF Summit, "a very broken
    abstraction", due to its complexity. It also has some performance
    problems. Stoakes was there to present, in raw form, a proposed
    replacement that he calls a "COW context".

    https://lwn.net/Articles/1072378/
    --- SBBSecho 3.37-Linux
    * Origin: Palantir * palantirbbs.ddns.net * Pensacola, FL * (618:250/24)