# Qwen3.8-27B (FP8 + DSpark draft) — 1× DGX Spark / GB10 (sm_121), TP=1. # # DSpark: a dedicated semi-autoregressive draft model (~2.6 GB, 5 layers, # block_size 7) proposes blocks of tokens that the full model verifies in one # weight-read. 3× cheaper per guess than the in-checkpoint MTP head, so it wins # on edit-heavy / structured workloads (blog: 45-48 t/s edit, 17 t/s free-gen, # 66 t/s aggregate @ c10 on the FP8 target). DSpark blocks are verifier-rejected, # so no quality risk. # # Target: Qwen/Qwen3.8-27B-FP8 (official FP8 quant, 28.75 GB). # Draft: RadixArk/Qwen3.8-27B-DSpark (arch DSparkDraftModel, bf16, 5 layers, # dspark_block_size 7). Downloaded via hfrs into the node HF cache. # # Image: ghcr.io/timothystewart6/vllm-gb10:v0.27.1-gb10.2 # vLLM 0.27.1 (installed 0.27.2.dev0+g6e448d0ea), supports method "dspark" # (SpeculativeMethod Literal includes dspark) + Qwen3DSparkModel draft. # # PREREQUISITES: # Target + draft cached on the node (dgx1 ~/.cache/huggingface → NAS): # hfrs download Qwen/Qwen3.8-27B-FP8 # hfrs download RadixArk/Qwen3.8-27B-DSpark # # REFERENCE: # https://blog.kubesimplify.com/qwen3-8-27b-on-dgx-spark (DSpark section) # https://huggingface.co/RadixArk/Qwen3.8-27B-DSpark # https://forums.developer.nvidia.com/t/qwen3-8-27b-on-dual-sparks/380350 engine = "vllm" name = "Qwen3.8-27B (FP8 + DSpark)" docker_image = "ghcr.io/timothystewart6/vllm-gb10:v0.27.1-gb10.2" model = "Qwen/Qwen3.8-27B-FP8" 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) "--attention-backend", "flashinfer", # Compilation / perf "--optimization-level", "3", "--performance-mode", "throughput", # Chunked prefill + prefix caching "--enable-chunked-prefill", "--enable-prefix-caching", "--enable-flashinfer-autotune", # DSpark speculative decoding — dedicated draft model (not the in-checkpoint # MTP head). num_speculative_tokens must equal the draft's block size (7). # The draft lives in a local dir (arch-patched copy of RadixArk/Qwen3.8-27B-DSpark # re-labelled `Qwen3DSparkModel` so vLLM routes it to qwen3_dspark, not the # DeepSeek-V4 DSpark code path) bind-mounted at /dspark-draft below. "--speculative-config", """ '{"method":"dspark","model":"/dspark-draft","num_speculative_tokens":7}'""", # 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) "--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", ] # DSpark draft model — arch-patched local copy of RadixArk/Qwen3.8-27B-DSpark, # mounted at /dspark-draft so vLLM loads it via the qwen3_dspark draft class. [[extra_mounts]] host = "/home/kilork/dspark-draft" container = "/dspark-draft" [env] HF_HUB_OFFLINE = "1" TORCH_CUDA_ARCH_LIST = "12.1a" CUTE_DSL_ARCH = "sm_121a" OMP_NUM_THREADS = "4" PYTORCH_CUDA_ALLOC_CONF = "expandable_segments:True" CUDA_VISIBLE_DEVICES = "0" CUDA_DEVICE_ORDER = "PCI_BUS_ID" CUDA_CACHE_MAXSIZE = "4294967296"