DeepSeek-V4-Flash-0731 — PrismaQuant AQUA (GridBook CB), 87 GB

A mixed-precision, per-Linear quantization of deepseek-ai/DeepSeek-V4-Flash-0731 (284B-A38B, 43 layers, 256 routed + 1 shared expert, FP8-native source) that fits the full model body in 87.08 GB — sized for a single 128 GB unified-memory machine (NVIDIA GB10 / DGX Spark) with headroom to serve.

Formats are chosen per Linear by the PrismaQuant AURA allocator (KL-adjoint Fisher cost × production-rendered ΔW, with activation-aware [AQUA] pricing on both weight and activation sides), then the shipped operating point is selected and measured on real end-to-end KL against the BF16 teacher — not on a local proxy.

Measured quality (this exact artifact, served)

Gold contract: WikiText, 8 × 512 tokens (4,088 scored positions), teacher = BF16 source, teacher distribution truncated to top-8192 logits per position; student served by vanilla vLLM with the pinned GridBook plugin (the same stack documented below), score_positions=all.

Internal ablation at the identical 87.4 GB byte budget: against the weight-only-cost allocation it replaced, the activation-aware (aqua-both) allocation shipped here measures −3.4% mean KL / −7.2% confident-KL / −11.0% p99-KL — all outside the ±0.7% cross-session repeat envelope — while direct PPL is statistically unchanged (+1.0%, inside the ~1.5% spread observed when re-serving identical bytes across sessions).

Precision map

Body assignment: 2.346 bits per parameter over the body's assignment tensor payload (including deduplicated codebook sidecars). Per-serving-unit format counts:

Activation contracts as served by the pinned runtime: NVFP4_CB units execute W4A4 (E2M1 group-16 activations, static UE4M3 global scale) on the 32 routed-MoE stages; FP8_CB and FP8-source units decode to BF16 and run a BF16 GEMM (weight-only). 189 declared passthrough tensors; no orphan scale planes.

Layer map

One column per layer (0–42), one row per projection; every cell is one serving unit, colored by the format the allocator chose, rendered from this artifact's own quant_config.json. Bright mint = verbatim FP8-source passthrough (lossless); teal = FP8 codebook rungs, brighter with codebook size K; navy/violet = NVFP4 codebook rungs; hatched = pinned at source precision and never offered to the allocator (router gates, the attention compressor, the indexer's compressor and score head — plus embedding and lm_head off-grid). Routed-expert rows are the packed per-layer expert stack: all 256 routed experts in a layer share one format, a serving invariant, not a simplification.

How to read it: the projections feeding attention state (wq_a, wkv, wo_a) ship as lossless FP8 source everywhere; shared experts stay rich (K48 or source); and the routed-expert mass — the bulk of the bytes — runs NVFP4-CB K12 through the first ~21 layers while the allocator concentrates its 8-bit budget on late-layer experts (FP8-CB K28 on layers 22–38, where the sensitivity card priced flips as most expensive). On the 11 FP8-CB expert layers gate/up ship as separate stacks and fuse at load; NVFP4-CB layers ship fused gate_up. K sizes the codebook — the weight coding only; the activation contract is set by the format family (table above).

The same map is browsable cell-by-cell, alongside every other PrismaQuant artifact, in the allocation explorer.

What this artifact does and does not claim

• Claimed: the KL/PPL numbers above, the byte size, and that vanilla vLLM with the pinned GridBook plugin loads and serves it (eager and CUDA-graph mode) on Blackwell.
• Not claimed: matched-budget serving performance parity. This is a body-only artifact (see below), and the matched-budget performance-parity gate structurally requires construction units and telemetry this artifact class cannot produce; it is recorded as scoped-out on the shipcard, not passed. Decode on NVFP4_CB units routes to the native codebook LUT path. Under the gated runtime (gridbook==0.8.8) large-batch prefill on codebook units rode a grouped dequant-to-BF16 bridge; GridBook 0.8.9 defaults the fused persistent-B decode-in-mainloop kernels on, so this artifact's 32 FP4-CB routed expert layers take that lane with no flags set (its 11 FP8-CB routed layers ship per-role codebooks and keep the bridge, announced per layer; dense CB prefill keeps the bridge). Same activation contract either way — a default-environment 0.8.9 serve of this exact artifact re-measured kl_mean +0.17 % / PPL −0.06 % against the recorded gold, inside the ±0.7 % cross-session KL envelope.
• The KL teacher is top-8192-truncated (mass renormalized); tail mass beyond rank 8192 is not scored.
• The MTP / speculative-decode sidecar is not included. The source's mtp. namespace (4,705 tensors) is excluded from this body-only artifact and recorded in quant_config.json provenance.

Serving

Tested stack: vanilla vLLM (Blackwell / SM121, CUDA 13) with the GridBook out-of-tree quantization plugin, gridbook==0.8.10.

pip install gridbook==0.8.10
vllm serve rdtand/DeepSeek-V4-Flash-0731-PrismaQuant-AQUA-gridbook-87GB-spark-vllm \
  --quantization gridbook --trust-remote-code \
  --tokenizer-mode deepseek_v4 \
  --generation-config vllm \
  --kv-cache-dtype fp8 \
  --kv-cache-memory-bytes 10737418240 \
  --max-model-len 131072 \
  --max-num-seqs 2 \
  --max-num-batched-tokens 2048 \
  --gpu-memory-utilization 0.90 \
  --enable-auto-tool-choice --tool-call-parser deepseek_v4 \
  --reasoning-parser deepseek_v4 \
  --default-chat-template-kwargs '{"reasoning_effort":"low"}' \
  --compilation-config '{"mode":0,"cudagraph_mode":"FULL_DECODE_ONLY","cudagraph_capture_sizes":[1,2]}' \
  --host 0.0.0.0 --port 8000

Every flag above is load-bearing on a 128 GB single-Spark box. The short form that omits them does not serve this model well, and in two cases does not serve it at all.

• --max-model-len 131072 — the config default is 1,048,576. Left at the default, vLLM sizes the KV pool against the machine's entire RAM (GPU and host share one pool on a Spark), reaches ~106 GiB of hard allocation on a 121.6 GiB box, and the container is OOM-killed after weights have already loaded successfully. It looks like a load failure; it is a sizing failure.
• --kv-cache-memory-bytes 10737418240 — a fixed 10 GiB pool (~637k tokens). Passing it also skips memory profiling entirely, which is what removes the autotune/warmup spike that triggers the kill above.
• --compilation-config … FULL_DECODE_ONLY — decode is launch-overhead-bound on this hardware. Capture is what makes decode throughput reproducible; without it decode runs materially slower.
• --default-chat-template-kwargs '{"reasoning_effort":"low"}' — vLLM defaults DeepSeek-V4 to reasoning_effort="high" whenever a request omits it, which injects a maximum-deliberation system prompt. The model obeys: a default-path "what is 2+2" can run for over twenty minutes without terminating. This is stock upstream vLLM behaviour, not a quantization artifact. "none" disables thinking entirely.
• --enable-auto-tool-choice --tool-call-parser deepseek_v4 --reasoning-parser deepseek_v4 — required for tool calls and reasoning segments to parse.

Known issue on newer vLLM — read before serving without the flags above. On vLLM 0.27+, whose default cudagraph_mode is FULL_AND_PIECEWISE, CUDA-graph capture fails in GridBook's MoE router (_padded_route performs a host sync inside the capture region) and the engine exits during startup rather than serving. Tracked as gridbook#47. The explicit --compilation-config above avoids it; --enforce-eager also works but costs substantial decode throughput, since decode on this hardware is launch-overhead-bound. If you are benchmarking this artifact, check which of those two you are on before quoting a tokens/sec number.

No forked runtime, no custom vLLM build: GridBook registers the quant method through vLLM's plugin interface. Weights are a single model.safetensors plus cb_codebooks.pqcb (codebook sidecar) and quant_config.json.

Provenance

• Built by PrismaQuant — probe → AURA/AQUA cost → knapsack allocation → codebook export — at commit a24fce2b, allocation recipe aqua-both.
• Artifact model_sha 3d3b8bde1343fe33… (full value and the complete gate record in shipcard.json inside the repo).
• Quantized from the FP8-native source; FP8 source tensors selected by the allocator ship as verbatim lossless copies.

Author: Robert Tand — robert.tand@icloud.com