Qwen3.8-27B-NVFP4-NInfer

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  • - for personal agents
  • - within ~5% of FP16
  • - 25 GB, 44% of 56 GB BF16
  • - ~3.7x speedup (69.5 → 255 tok/s @ c1)

Performance (Measured on 1× GeForce RTX 5090)

Agentic coding throughput

Replay of recorded mini-swe-agent turns, mean context ~28k, thinking on, prefix cache on, DFlash2 K=7 + lm-head-draft patches.

Concurrencyout tok/saccept lengthTTFT msITL ms
12554.4014384.3
46864.3524215.4

Cold prefill and long-context decode

long profile, --no-prefix-reuse, 8 prompts, out=256, concurrency 1, greedy. Prefill tok/s ≈ prompt_len / mean_TTFT.

promptdecode tok/sprefill tok/sTTFT mean / p50 / p90 / p99 (ms)ITL mean / p50 / p90 / p99 (ms)
1024211~16k65 / 56 / 105 / 11617.1 / 17.1 / 17.2 / 17.3
4096147~16k254 / 248 / 394 / 41317.2 / 17.2 / 17.3 / 17.4
1638481~16k998 / 1010 / 1606 / 177717.4 / 17.4 / 17.7 / 17.8
3276856~18k1778 / 1586 / 3068 / 363917.6 / 17.6 / 18.0 / 18.2

Optimisation

  • - NVFP4 dense 27B on NInfer (Goethe nvfp4-kernels); hybrid NVFP4 MLP + FP8 attention/head
  • - DFlash2 speculative decoding (default, K=7) or MTP (batch profile, K=4); --lm-head-draft
  • - FP8 KV cache, CUDA Graph decode, prefill chunk 1024, prefix reuse
  • - MLP down-projection retile for ≤16-token drafts (~1.4% faster decode, bit-identical)
  • - Draft shortlist patched to include <tool_call> tokens (~3.5% on agent traffic; ~5% combined vs unpatched)