Linux's Leap Beyond Fixed Pages
summary
Linux gains multi-sized transparent huge pages (mTHP) that allocate physically contiguous power-of-two page chunks at fault time, plus an enhanced background daemon (khugepaged) to build them asynchronously. On arm64 the contiguous-bit lets the TLB coalesce 64KB of translations, cutting TLB pressure; kernels with mTHP show real benchmarks — roughly 12% perf uplift on some configs and ~8% with 4KB→64KB tradeoffs — while suffering CoW, swap and allocation shattering, locking and fragmentation issues that ongoing patches and migration/locking changes aim to fix.
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chapters (9)
- 0:00Introduction to talk
- 1:03Virtual memory basics
- 9:15TLB and caching role
- 12:29Fixed page size limitations
- 14:59Huge pages introduction
- 18:13Transparent huge pages
- 20:04Multi-size transparent huge pages
- 25:51Kernel huge page daemon
- 33:48Q&A session
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