Gemma 4 12B · vLLM · NVFP4 · RedHatAI

status: done

Configuration

Modelgoogle/gemma-4-12B-it
CompanyGoogle
FamilyGemma
Parameters12B (dense)
EnginevLLM
Quant / precisionNVFP4
Why this quantRedHatAI/gemma-4-12B-it-NVFP4 — trusted Red Hat AI NVFP4 quant, with the model card explicitly stating it is compatible with and tested against vLLM nightly. Queue it on vLLM rather than SGLang because that is the validated serving stack the repo names directly.
DownloadRedHatAI/gemma-4-12B-it-NVFP4
Context window65536
Input modalitiestext, image, audio, video (served text-only here)

Measured results

Prefill tok/s582.39
Decode tok/s503.81
Peak memory (GB)109.38 (system MemAvailable delta (10s sampling) — vLLM static KV reservation (util 0.85))
Completed2026-06-23 23:07 +0800

Full run command

# RedHatAI says this checkpoint is compatible with and tested against vLLM nightly.
scripts/bench-vllm-serving.sh RedHatAI/gemma-4-12B-it-NVFP4 65536 32 1000 900 256

gemma-4-12b Google Gemma NVFP4 5-15B conc-32

Notes

DONE — the smallest pending benchmark is now recorded, and this Red Hat AI NVFP4 path runs cleanly on the maintained vLLM nightly.

  • Workload: ShareGPT V3, conc-32, standard 1000-prompt / 15 min cap. This run completed 1000/1000 with 0 errors in 462.7 s and did not hit the time cap.
  • Throughput: prefill 582.39 tok/s, decode 503.81 tok/s aggregate. Median TTFT 179.3 ms, median TPOT 58.3 ms, request throughput 2.161 req/s.
  • Load behavior: server readiness took 226 s end to end before the benchmark began. Once up, it stayed stable under the full 32-way load.
  • Memory: 109.38 GB headline usage, which here is the expected vLLM KV reservation at --gpu-memory-utilization 0.85, not the checkpoint footprint. The engine log reported the model load itself at about 8.29 GiB before KV allocation/cudagraph overhead.
  • Engine/runtime notes: vLLM resolved the checkpoint as Gemma4UnifiedForConditionalGeneration on nightly-aarch64, forced the TRITON_ATTN backend because Gemma-4 has heterogeneous head dimensions, and used the FlashInferCutlassNvFp4LinearKernel NVFP4 GEMM path. A runtime warning flagged different global NVFP4 scales across some parallel layers, which may slightly reduce accuracy; throughput was unaffected in this run.