• Linux 7.0 Speeds Up Reclaiming File-Backed Large Folios By 50~75% Merged on Wednesday were some additional memory management “MM” updates for the Linux 7.0 merge window. • Most interesting out of these latest three dozen patches is support for batched unmapping of file-backed large folios. • The patches to support batch checking of references and unmapping for large folios is showing very nice performance numbers for reclaiming file-backed large folios. • This work was carried out by Alibaba engineer Baolin Wang. • He explained back on the patch series: When the patch series concludes with the batched unmapping for file large folios is where the numbers come out and are quite enticing: Some nice gains and with the increasing use of folios throughout the Linux kernel. • See this MM pull request for those interested in these latest patches now merged for Linux 7.0.
Article Summaries:
- Linux kernel 7.0 now includes memory‑management patches that accelerate the reclamation of file‑backed large folios by 50-75 %. The updates, contributed by Alibaba engineer Baolin Wang, add batched reference checks and unmapping for large folios, addressing a hotspot in the folio_referenced() path. Performance tests on an Arm64 32‑core server and an x86 machine showed 75 % and 50 % speed‑ups, respectively, when reclaiming 8 GB of clean file‑backed memory. The changes are merged in the 7.0 release and are expected to benefit workloads that rely heavily on folio usage throughout the kernel.
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