Qwen3.5 397B (17B active)

User reports 29.2 t/s generation. Source evidence (verbatim): Source: https://alooftwaffle.substack.com/p/96-hours-with-dual-dgx-sparks-and # First-hand Mac Studio M3 Ultra 512GB Qwen3.5-397B-A17B 6-bit mlx-vlm generation measurement Original first-hand report by AlooftWaffle, published March 27, 2026: https://alooftwaffle.substack.com/p/96-hours-with-dual-dgx-sparks-and . Historical source-reported measurements, not a new benchmark or independent reproduction. Selected configuration: one Mac Studio M3 Ultra with 512GB unified memory, running Qwen3.5-397B-A17B at publisher-described 6-bit precision using mlx-vlm. The shortest reported context row gives generation 29.2 tokens/s. The source labels this row 4K context; whether that label denotes actual occupied input or configured capacity is not established. Actual fresh input count, cached prefix, output count and runtime version are unknown. Leave structured context length unknown. Do not replace it with 4096 or infer zero cache. CPU/GPU core counts, sampling, thinking mode, speculative decoding, request concurrency, warmup, repeats, statistical aggregation, exact measurement date, OS, KV precision, Flash Attention, offload, temperatures, power and peak resident memory are unreported. The source's longer Mac rows report generation 28.6 tokens/s at the 8K label and 26.7 tokens/s at 32K; preserve these as separate source rows, not an average. The author also calls values 317/537/476 tokens/s 'prefill throughput (time to first token)'; native timing boundaries and counters are absent, so leave structured prompt throughput and TTFT unknown rather than converting or equating these metrics. Verified upstream model-family reference: https://huggingface.co/Qwen/Qwen3.5-397B-A17B . This is a base/reference repository, not the tested 6-bit artifact. The tested quantization repository, revision, file names, hashes and quantization recipe are unknown; do not assign a community pack or GGUF Q6 code. The source describes nearly 300GB of downloaded model files; that is download/storage volume, not measured resident RAM or a peak-memory measurement. The same article's dual-Spark INT4-AutoRound/vLLM measurements and embedding sentences/s are different hardware, quantization and workloads; none is the selected Mac generation speed or a controlled comparison isolating hardware. Full original source remains the URL above; no author contact or comments were made.