cache_ext: Customizing the Page Cache with eBPF

on YouTube ↗29m

" summary

An eBPF-based framework called cache_ext injects hooks for page insertion, access, and eviction so users load kernel-verified policies per cgroup without rebuilding the kernel. Eight policies are implemented (LFU, MRU, LHD, S3, etc.), including an application-informed get/scan split that yields up to 70% higher throughput and 58% lower tail latency on HTAP-like workloads. Implementation adds ~2k LOC, handles safety via vetted pointers and eviction lists, and shows no single policy wins all.

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" chapters (9)

1. 0:00Introduction to cache_ext
2. 2:30Limitations of current page cache
3. 4:58Introducing cache_ext framework
4. 8:31Application-informed policies demo
5. 10:58Evaluating modern caching policies
6. 12:44Per-cgroup policy implementation
7. 15:32Memory safety challenges
8. 16:35Future of BPF in page cache
9. 19:44Q&A session

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