Same pathological imbalance E1 showed reproduces in E2: D2 has zero
bindings at 33% POSTs in. Root cause is structural, not a KVC v2 bug:
all 50 Inferact sessions begin with identical "permissions
instructions" boilerplate, so the converter assigns them identical
first-block hash_ids. kv-aware policy's overlap term (lex-score
position 0) makes any already-resident D dominate a fresh D
unconditionally, and v2's migration only activates on admission
rejects which never fire because D0/D1 KV pools have headroom. The
H1 conclusion is qualified: KVC v2 helps per-request work (direct-
to-D fast path) but does not rebalance D worker load on workloads
with shared cross-session prefixes.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
E1 finished 1h29min wall on the 50-session Inferact subset. Headline:
1200/1285 succeeded, latency p50=93s p99=219s, TTFT p50=89s p99=207s,
85 timeouts. Decode-2 was never bound to a single session — all 50
sessions stuck to decode-0/1 by kv-aware policy stickiness with no
migration to rebalance, so effective topology was 1P2D, not 1P3D.
This is exactly the failure mode H1 predicts naive pd-disaggregation
should exhibit, giving E2 (full KVC v2 with migration) a concrete
baseline to improve against.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
