TCP memory isolation on multi-tenant servers

on YouTube ↗44m

" summary

Proposes removing the global tcp_mem limit and charging TCP socket buffers to cgroup memory limits, implements a measurement mode to gather per-job TCP memory without enforcing limits, and exposes a per-cgroup opt-in/opt-out control for gradual rollout. Kernel patches port v2-style accounting into v1 fleets and add a per-CPU cache fix. Finds surprising effects: per-socket precache up to ~1MB inflates memcg usage, and a patch series causes reported 60–70% perf regressions; measurement and staged rollout catch bugs while automated load‑shaping eases user impact.

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" chapters (8)

1. 0:00Introduction to talk
2. 1:04Background and problem overview
3. 7:32Solution for memory isolation
4. 11:51Deployment challenges
5. 20:18Bugs from accounting changes
6. 28:13Work in progress
7. 33:59Conclusion and takeaways
8. 35:50Q&A session

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