# Qwen3.8-27B (BF16) — 1× DGX Spark / GB10 (sm_121), TP=1. # # Native BF16 dense 27B (52 GB). Quality reference baseline; the quantized # variants (FP8 / NVFP4 / Int4) are the speed candidates. Runs text + vision. # # Image: ghcr.io/timothystewart6/vllm-gb10:v0.27.1-gb10.2 # vLLM 0.27.1, torch 2.13+cuda130, FlashInfer built from source, # instanttensor. Stock vLLM — supports the qwen3_5 arch + MTP. # # Model: Qwen/Qwen3.8-27B # https://huggingface.co/Qwen/Qwen3.8-27B # Dense 27B, 64 layers, hidden 5120, GQA (4 KV heads × 256), Gated # DeltaNet + Gated Attention hybrid. MTP-1. Native 262,144 ctx (YaRN to 1M). # Multimodal (vision tower, `language_model_only: False`). # # PREREQUISITES: # Weights cached on every node (dgx1 ~/.cache/huggingface → NAS): # huggingface-cli download Qwen/Qwen3.8-27B # # REFERENCE: # https://forums.developer.nvidia.com/t/qwen3-8-27b-mixedint4-autoround-optimized-for-a-single-dgx-spark/380248 # https://forums.developer.nvidia.com/t/qwen3-8-27b-on-dual-sparks/380350 # https://forums.developer.nvidia.com/t/qwen3-8-27b-at-34-38-tok-s-on-dgx-spark-open-source-one-command-setup-sglang-nvfp4-dspark/380257 engine = "vllm" name = "Qwen3.8-27B (BF16)" docker_image = "ghcr.io/timothystewart6/vllm-gb10:v0.27.1-gb10.2" model = "Qwen/Qwen3.8-27B" required_nodes = 1 tensor_parallel_size = 1 pipeline_parallel_size = 1 distributed_backend = "mp" shm_size = "32gb" entrypoint = ["vllm", "serve"] args = [ # KV cache & memory "--kv-cache-dtype", "fp8", "--max-model-len", "262144", "--max-num-seqs", "6", "--max-num-batched-tokens", "8192", "--gpu-memory-utilization", "0.75", "--served-model-name", "qwen3.8-27b", # Engine backends (dense GQA — FlashInfer, not the DeepSeek MLA path) "--attention-backend", "flashinfer", # Compilation / perf "--optimization-level", "3", "--performance-mode", "throughput", # Chunked prefill + prefix caching "--enable-chunked-prefill", "--enable-prefix-caching", "--enable-flashinfer-autotune", # MTP speculative decoding (in-checkpoint draft, mtp_num_hidden_layers=1 # cycled across steps) "--speculative-config", """ '{"method":"mtp","num_speculative_tokens":5}'""", # Tokenizer / reasoning (Qwen3 family) "--tool-call-parser", "qwen3_xml", "--reasoning-parser", "qwen3", "--enable-auto-tool-choice", "--generation-config", "auto", "--default-chat-template-kwargs.preserve_thinking=true", # Proven generation defaults (thinking mode; Qwen3.8 model-card best # practices). repetition_penalty 1.0 = identity: accepted but never # deviates from no-op during req handling (DSpark/MLA bug caveat — see # findings doc for the DeepSeek path; irrelevant to dense Qwen). "--override-generation-config", """ '{"temperature":1.0,"top_p":0.95,"top_k":20,"min_p":0.0,"presence_penalty":0.0,"repetition_penalty":1.0}'""", "--trust-remote-code", ] [env] # Offline mode — weights must be cached on each node HF_HUB_OFFLINE = "1" # Architecture TORCH_CUDA_ARCH_LIST = "12.1a" CUTE_DSL_ARCH = "sm_121a" OMP_NUM_THREADS = "4" # GPU memory management PYTORCH_CUDA_ALLOC_CONF = "expandable_segments:True" # GPU device isolation CUDA_VISIBLE_DEVICES = "0" CUDA_DEVICE_ORDER = "PCI_BUS_ID" CUDA_CACHE_MAXSIZE = "4294967296"