Everything Matters in Programmable Packet Scheduling

on YouTube ↗15m

" summary

Presents PACKS, a quantile-based admission and queue-mapping design that approximates both PIFO queues scheduling and admission behaviors using a sliding-window rank distribution and per-queue occupancy. Fully implemented in P4 and evaluated in packet-level simulation and on Intel Tofino hardware, PACKS runs at line rate, reduces rank inversions by up to 7× and 15× versus SP-PIFO and AIFO, cuts packet drops up to 60% versus SP-PIFO, and lowers mean FCT for small flows by up to 33% and 2.6×.

AI-written summary · about

" chapters (11)

1. 0:00Programmable packet scheduling intro
2. 1:27Why it matters
3. 2:51PyQ abstraction behaviors
4. 4:16Limitations of prior PyQ approx
5. 7:03Admission and scheduling matter
6. 8:26PGX approximates PyQ admission
7. 10:11Real-time adaptation in PGX
8. 11:36PGX in a single slide
9. 12:17Evaluating PGX in software/hardware
10. 13:01Key results: drops and inversions
11. 14:44Impact on flow completion times

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