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Synthesize the cross-engine bit-exactness and f32-preserving-parity study. Resolve the contradiction between sub-agents (one f32, two bf16) by reading every link of vLLM's state-dtype chain on live source: - config.json text_config.mamba_ssm_dtype = "float32" (both served models) - cache.py default mamba_ssm_cache_dtype = "auto"; bench passes no override - vllm.py __post_init__ -> try_verify_and_update_config (config finalize) - Qwen3_5ForConditionalGenerationConfig override copies "float32" into mamba_ssm_cache_dtype before state-dtype resolution - mamba_utils._mamba_state_dtype -> temporal = torch.float32 (conv = bf16) - qwen_gdn_linear_attn allocates the temporal cache at f32 Verdicts: B1 TRUE (sub-claim 'more efficient than vLLM' refuted); B2 REFUTED (equal f32 bytes both sides, ~10pct efficiency gap not 2x width); B3 REFUTED (vLLM hits throughput with f32 state; a bit-exact occupancy/coalescing retune of gated_delta_net_cuda 74->81pct peak is the f32-preserving parity lever); B4 CONFIRMED (bit-exact-vs-vLLM impossible: A1 FP4 GEMM 8/4/16-bit operand gap + A2 recurrence g.Sigma vs Sigma.g reassociation on different reduction trees, plus general FP non-associativity). bf16 temporal state degrades BELOW vLLM's f32 recurrent precision -> an over-clock, not a parity requirement. Assisted-by: Claude:opus-4.8 [Claude Code] Signed-off-by: Ettore Di Giacinto <mudler@localai.io>