KAT-Coder-V2.5-Dev W8A128 with AutoRound int8

Weight-only 8-bit quant of KAT-Coder-V2.5-Dev using AutoRound v0.15.0, quantized at int8 against a python-focused sampleset.

Under the hood

256-expert MoE on Qwen3.5. 40 layers, 30 use linear attention and 10 use full attention (every 4th). Shared expert gates kept at FP16.

Quantization is symmetric INT8, group size 128. Calibrated on 384 samples over 400 iterations with sequence length 4096 instead of the default 2048.

Dataset Config KL ↓ Top-1 match Top-1 in ref top-5 Tokens
Wikitext-103 4 × 4096 0.00470 96.84% 99.97% 16,336
Wikitext-103 2 × 8192 0.00437 97.35% 99.98% 16,360
code-search-net (6 lang) 4 × 4096 0.00443 98.18% 99.99% 16,336
code-search-net (6 lang) 2 × 8192 0.00433 98.28% 100.00% 16,360

Hardware

Fits on two 3090s with headroom. This quant was created largely to fit this into two 24gb cards while maintaining speed. On my machine, this retains enough space for 3 max-num-seqs at full context. Tinker as you see fit to get the number of parallel slots you'd like to serve.

Inference

vLLM V1 engine:

PYTORCH_CUDA_ALLOC_CONF=expandable_segments:True \
vllm serve \
  jpbwin/KAT-Coder-V2.5-Dev-int8-AutoRound \
  --port 5001 \
  --tensor-parallel-size 2 \
  --gpu-memory-utilization 0.975 \
  --max-num-seqs 3 \
  --enable-chunked-prefill \
  --enable-prefix-caching

Notes

I had to alter the auto-round library hella in order to get this to work end to end, but in the end, vanilla VLLM serves this just fine :)

Upstream PRs to auto-round to come, it seems to do a lot of double work and underutilizes gpu capability when quantizing some models.

License

Apache 2.0

Downloads last month
47
Safetensors
Model size
10B params
Tensor type
I32
·
BF16
·
F16
·
Inference Providers NEW
This model isn't deployed by any Inference Provider. 🙋 Ask for provider support

Model tree for jpbwin/KAT-Coder-V2.5-Dev-int8-AutoRound

Quantized
(32)
this model