~/talk

Pyrrha: Congestion-Root-Based Flow Control to Eliminate Head-of-Line Blocking in...

on YouTube 17m
Talkat NSDI '25 · 2025-04-28..04-30· [networking]

speakers

name:Kexin Liu
links:none on file
name:Zhaochen Zhang
links:none on file
name:Chang Liu
links:none on file
name:Yizhi Wang
links:none on file
name:Vamsi Addanki
links:none on file
name:Stefan Schmid
links:none on file
name:Qingyue Wang
links:none on file
name:Wei Chen
links:none on file
name:Xiaoliang Wang
links:none on file
name:Jiaqi Zheng
links:none on file
name:Wenhao Sun
links:none on file
name:Tao Wu
links:none on file
name:Ke Meng
links:none on file
name:Fei Chen
links:none on file
name:Weiguang Wang
links:none on file
name:Bingyang Liu
links:none on file
name:Wanchun Dou
links:none on file
name:Guihai Chen
links:none on file
name:Chen Tian
links:none on file

resources

video:https://youtu.be/_2yUbst0PF4
slides:none on file

summary

Claims a flow-control granularity tied to the congestion-root ID that provably eliminates head‑of‑line blocking by allocating isolation queues only for flows that actually route through the congested port, using a distributed route‑election and merge protocol. Prototype runs on Tofino2 and uses ~40% memory to support ~10,000 hosts; worst‑case per‑port queue usage stays under 20 queues. Reported results: 42%–98% average FCT reduction for uncongested flows and 1.6×–215× lower 99th‑percentile latency.

AI-written summary · about

chapters (7)

  1. 0:00Pyrrha introduction
  2. 2:02Per-hop flow control benefits
  3. 3:49Drawbacks of PFC
  4. 6:41Congestion root insight
  5. 8:55Pyrrha protocol design
  6. 14:16Implementation and performance
  7. 15:42Conclusion and future

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