DeepSeek V4.1 Flash Hits 141.3 Tok/s on Two DGX Sparks
The fastest vLLM build yet runs 2.5x the prior best kit, with weights and recipe public.
@sudoingX reports deepseek v4.1 flash flying on 2x DGX Spark, served with vLLM: 141.3 tok/s on structured output, 103.0 on code, 58.3 on prose. He calls it the fastest vLLM build of the model on two Sparks, 2.5x the best prior kit, and ahead of TensorFold v0.6.0 on code and structured output. It serves full context at 262k tokens per request.
The needle test found 3 of 3 at 8k, 32k, 64k, 128k and 256k, the last a 255,709-token prompt, with decode holding between 75 and 82 tok/s. Prefill runs 1,395 to 1,475 tok/s, which he calls his weak side. Each of the 15,360 experts sits at 2 to 5 bits by measured sensitivity, 2.70 on average, and the engine is upstream vLLM main with 22 patches and no fork.
Quality held too: his quantization measures KL divergence of 0.0243 from native, 18% lower than the next best pack, with 95.57% top-1 agreement. It scores closer to native on 7 of 8 domains, and HumanEval+, MBPP+ and IFEval sit within noise. The 196 GB weights and the recipe are public.