Vue normale

[$] Policy groups for memory management

Par : corbet
14 mai 2026 à 19:02
The kernel's control-group subsystem works well for resource management, Chris Li said at the beginning of his memory-management-track session at the 2026 Linux Storage, Filesystem, Memory Management, and BPF Summit. Control groups work less well for other use cases, though. He was there to present his proposed enhancement, called "policy groups", that would address some of the shortcomings that he has encountered. A consensus on how this feature should look still seems distant, though.

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

Par : corbet
14 mai 2026 à 13:14
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".

[$] LWN.net Weekly Edition for May 14, 2026

Par : corbet
14 mai 2026 à 01:04
Inside this week's LWN.net Weekly Edition:

  • Front: Fedora AI; Forgejo "carrot" disclosure; memory-management maintainership; huge THPs; mshare; 64KB base pages; DAMON; direct map.
  • Briefs: Dirty Frag; Fragnesia; Mythos and curl; killswitch; Debian reproducible builds; KDE investment; Quotes ...
  • Announcements: Newsletters, conferences, security updates, patches, and more.
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