Swift-Qwen3.8-27B-PARO-MXFP6

ukisai/Swift-Qwen3.8-27b with ParoQuant rotations and MXFP6 (E2M3) weights, for AMD Radeon AI PRO R9700 (RDNA4) on a patched vLLM.

Size: 25.1 GB (bf16: 55.6 GB).

This is a 27B model; the Hub's params badge counts packed tensor elements.

Quality

this model bf16
WikiText-2 perplexity 7.083 7.098
KL divergence vs bf16 (top-256, nats) 0.0117 0
Top-1 token match with bf16 95.06% 100%
MMLU 5-shot 82.6% —
GSM8K flexible / strict 96.7% / 95.9% — / —
HumanEval / HumanEval+ 97.0% / 93.9% — / —

bf16 = the unquantized source model served on the same image; — = not measured. Perplexity is cross-stack — this model at tensor parallel 1, bf16 at 2 — and wikitext-2's train split is in the stage-2 calibration mix, so a reading at or below bf16 is not evidence of a general gain. GSM8K and HumanEval are chat-templated with reasoning on, greedy, on a Qwen chat template at reasoning_effort=xhigh rather than the default template the command below uses; both scores move with that choice.

Performance

2× Radeon AI PRO R9700, TP=2, DFlash2-FP8 drafter (7 tokens), KV pinned with KV_MEM=13500000000, tokens/s.

Single-stream decode 138.0
Concurrent decode c1 / c2 / c4 / c8 124.7 / 209.6 / 321.6 / 394.0
Prefill 2k / 8k / 16k / 32k / 60k 3327 / 3628 / 3570 / 3479 / 3348
KV cache tokens 685,554
Weights per GPU 12.85 GiB

Each row is a single measured run — the speed rows at a 12.5 GB pin — on a newer radiance build than the 0.9.3 image the setup below installs, so expect these figures to move. KV capacity follows the pin, not the weight format.

How to run

Requirements

  • Two AMD RDNA4 (gfx1201) GPUs. The kernels are built for that architecture only; measured on 2 x Radeon AI PRO R9700 at tensor parallel 2.
  • Linux with the amdgpu kernel driver loaded, so /dev/kfd and /dev/dri exist. ROCm userspace ships inside the image, so there is no host ROCm install.
  • docker or podman (auto-detected), and a host git and python3 (standard library only).
  • Disk for the checkpoint, plus about 12 GiB for the DFlash2-FP8 drafter and the stilldeadcode/vllm-radiance:0.9.3 image, both of which setup fetches.

Two ways to get the code. MXFP6 support is open as a pull request to ggz14/radiance-vllm-mxfp4 (#46). Clone the fork below to run it today, or wait for the pull request to merge and clone ggz14's repository instead — the commands are the same either way.

Install and serve

git clone https://codeberg.org/hugypufy/radiance-vllm-mxfp4 && cd radiance-vllm-mxfp4

SRC_REPO=hugypufy/Swift-Qwen3.8-27B-PARO-MXFP6 SNAP=~/models/Swift-Qwen3.8-27B-PARO-MXFP6 \
  ./setup-paroquant.sh --mxfp6 --yes

MODEL_DIR=Swift-Qwen3.8-27B-PARO-MXFP6 MODE=prod SPEC=7 ./paroquant/run_paroquant.sh

Setup is one-time and safe to re-run. The launcher reads the quantization format from config.json and sets the kernel knobs it needs, so that is the whole serve command; the server answers as Qwen3.8-PARO on http://localhost:8080/v1. Every start patches vLLM inside the container and compiles the ParoQuant kernels for gfx1201, about two minutes, before the model loads; the first start also compiles Triton and inductor graphs, which adds several minutes and is cached for later starts.

Test

curl -s http://localhost:8080/v1/chat/completions -H 'Content-Type: application/json' \
  -d '{"model":"Qwen3.8-PARO","messages":[{"role":"user","content":"Hello!"}]}'

Options — set as environment variables on the serve command.

Variable Default Notes
KV_MEM unset; the pool is sized from GPU_UTIL (0.92) Pin the KV cache in bytes per GPU; this checkpoint is served at KV_MEM=13500000000
SPEC 5 DFlash2 draft tokens per step. The numbers above used 7
CHAT_TEMPLATE the repository's qwen-fixed-v22.3.jinja Any .jinja on the host, for example this checkpoint's own chat_template.jinja
RADIANCE_VERIFY_HEAD 1 Set to 0 to use prompt_logprobs, which hangs at the default

Format

  • Weights: OCP MXFP6 E2M3, one e8m0 scale per 32 weights — 6.25 bits/weight.
  • Rotations: from z-lab/Qwen3.8-27B-PARO, frozen.
  • Recipe: round-to-nearest, then a stage-2 fine-tune (FT) of weights and block scales, rotations frozen.
  • fp16: visual tower, linear_attn.in_proj_a/b, linear_attn.conv1d / A_log / dt_bias, lm_head, embeddings, norms, and the rotation theta / channel_scales (pairs are int16). MTP head not included.

Licence

Governed by the base model's Swift Open License v1.0 (terms); included as LICENSE, with Qwen's Apache-2.0 as LICENSE-APACHE-2.0. Modified derivative, not made or endorsed by UkisAI; NOTICE lists the changes. Rotations from z-lab/Qwen3.8-27B-PARO (Apache-2.0); original base Qwen/Qwen3.8-27B.

Downloads last month
178
Safetensors
Model size
21B params
Tensor type
F16
·
I16
·
U8
·
Inference Providers NEW
This model isn't deployed by any Inference Provider. 🙋 Ask for provider support

Model tree for hugypufy/Swift-Qwen3.8-27B-PARO-MXFP6

Base model

Qwen/Qwen3.8-27B
Quantized
(54)
this model