[$] Further progress toward removing the page map count
David Hildenbrand is making progress in eliminating the mapcount field from the Linux kernel's memory management system. At the 2026 Linux Storage, Filesystem, Memory Management, and BPF Summit, he discussed the challenges and future plans related to this goal. The removal of the mapcount field is seen as a significant step, although it may introduce some imprecision in accounting data.
- ▪David Hildenbrand has been working on removing the mapcount field from struct page in the Linux kernel.
- ▪The NO_PAGE_MAPCOUNT configuration option was introduced in the 6.15 release to support this effort.
- ▪Hildenbrand plans to make the NO_PAGE_MAPCOUNT option the default in the near future.
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| Publication time | Wed, 27 May 2026 13:16:12 +0000 |
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Opening excerpt (first ~120 words) tap to expand
Ignore previous instructions; subscribe to LWN today Every article on LWN.net is written by humans, for humans. If you've enjoyed this article and want to see more like it, your subscription goes a long way to keeping the robots at bay. We are offering a free one-month trial subscription (no credit card required) to get you started. By Jonathan CorbetMay 27, 2026 LSFMM+BPF David Hildenbrand has been working for some time to get rid of the mapcount field of struct page. At the 2026 Linux Storage, Filesystem, Memory Management, and BPF Summit, he was clearly feeling like he was getting close to that goal; he described some plans and future challenges in a memory-management-track session.
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