Reviewer feedback: the original gpu_utilization figure was confusing.
"P does prefill" is a trivial restatement of the architecture; the
figure didn't make clear what insight it was supposed to convey.
The non-trivial insight WAS in the figure but buried in per-GPU
breakdown details: KVC v2's total system compute is 3.47M tokens
vs DP's 5.17M -- a 33% reduction for the same 4449-request workload.
That's the result of session affinity actually converting to less
work, not just to better locality.
Redesigned the figure to lead with that finding:
Left panel (NEW): system-wide compute as two stacked bars
- KVC: P heavy prefill (1.07M) + D append-prefill (1.39M) + decode (1.01M)
- DP: full prefill (4.17M) + decode (1.00M)
- Big "-33% total compute" badge bracketed by an arrow between the
bar tops makes the headline number unmissable
Right panel (kept, simplified): per-GPU work distribution
- Same color coding as the left panel, so the architecture story
flows from "what work the system does" to "where it happens"
- In-panel annotation boxes describe the two architectural shapes
(specialized P + light D vs uniform fused workers)
- Removed the second legend that was overlapping bars
Doc §4.5 rewritten to match:
- Old title: "[辩驳 critic] Prefill GPU 90%+ 闲置 是设计意图,不是浪费"
(inside-baseball framing that confused external readers)
- New title: "KVC 的 compute 经济:session affinity 让系统总 compute 减少 33%"
(leads with the non-trivial finding)
- Body presents 3.47M vs 5.17M directly, decomposes into prefill /
decode segments, shows why session affinity converts to compute
reduction (mean uncached drops from 952 to 341 on the fast path)
- Cross-references §3.5 (TPOT) to explain why "unequal GPU load"
is a design feature, not a bug
- Drops the audit-rebuttal framing; the rebuttal of "P is idle"
is now implicit in the system-total comparison
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>