Runtime Programmable Switches

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" summary

Prototype called FlexCore performs partial reconfiguration primitives on P4 pipelines by atomically switching PD-table pointers and installing flex edges, enabling runtime upgrades without draining or reflashing and with zero packet loss. Implementation targets Nvidia Spectrum‑2 silicon and a bmv2-based software simulator. Multi-step upgrades use multi-level consistency (program, element, execution) to avoid transient bad states. Case study swaps unicast for multicast in‑flight, improves completion time, reports no packet loss during changes, and shows removing multicast saves ~20 ns pipeline latency.

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" chapters (17)

1. 0:00Intro
2. 0:24Background: Programmable switche
3. 1:22From compile-time to runtime programm
4. 1:53Benefits of runtime programmability
5. 2:50FlexCore: A whole-stack design
6. 3:44Flexible switch architect
7. 4:17Solution: Disaggregated RMT architect
8. 5:08Partial reconfiguration with indirectid
9. 7:41More partial reconfiguration primitive
10. 8:17Atomic changes
11. 9:06Solution: Version control with FlexEd
12. 10:11Finer-grained partial upd
13. 11:31Solution: Multi-level consistency for multi-s
14. 12:17Implementation and setup
15. 12:59Case study: Accelerated multicast
16. 14:03More results in the paper
17. 14:15Summary

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