vLLM/Recipes
DeepSeek

deepseek-ai/DeepSeek-V3.2-Exp

Experimental DeepSeek-V3.2 preview with sparse attention (MQA-like logits) and FP8 KV cache; architecture matches DeepSeek-V3.1 except for the sparse attention mechanism.

Sparse attention MoE with FP8 KV cache and strong GSM8K score (~0.96)

moe671B / 37B163,840 ctxvLLM 0.12.0+text
Guide

Overview

DeepSeek-V3.2-Exp is a sparse-attention MoE preview. Its main architecture is similar to DeepSeek-V3.1, with a sparse attention mechanism. This guide covers deployment on NVIDIA Hopper/Blackwell GPUs and AMD MI300X / MI325X / MI355X GPUs.

Prerequisites

  • Hardware: 8x H200/H20/B200 (CUDA) or 8x MI300X / MI325X / MI355X (ROCm)
  • vLLM: Current stable release
  • DeepGEMM (CUDA only): Required for MQA logits computation (and optionally for MoE)

CUDA

source .venv/bin/activate
uv pip install -U vllm --torch-backend auto
uv pip install git+https://github.com/deepseek-ai/DeepGEMM.git@v2.1.1.post3 --no-build-isolation

ROCm (MI300X, MI325X, MI355X)

Requires Python 3.12, ROCm 7.2.1, and glibc >= 2.35. If your environment does not meet these requirements, use the Docker-based setup described in the documentation.

uv venv --python 3.12
source .venv/bin/activate
uv pip install vllm --extra-index-url https://wheels.vllm.ai/rocm/

Note: DeepGEMM is used both for MoE and for MQA logits computation. It is required for MQA logits on CUDA. To disable the MoE path only, set VLLM_USE_DEEP_GEMM=0. Some users report better performance with VLLM_USE_DEEP_GEMM=0 (e.g. on H20), and this also skips the long warmup.

Launching DeepSeek-V3.2-Exp

8xH200 / 8xH20 (CUDA)

Using the recommended EP/DP mode:

vllm serve deepseek-ai/DeepSeek-V3.2-Exp -dp 8 --enable-expert-parallel

Using tensor parallel:

vllm serve deepseek-ai/DeepSeek-V3.2-Exp -tp 8

8xB200 (CUDA)

Same as 8xH200 / 8xH20.

8xMI300X / MI325X / MI355X (ROCm)

export SAFETENSORS_FAST_GPU=1
export VLLM_ROCM_USE_AITER=1
export VLLM_ROCM_USE_AITER_MOE=1
export VLLM_RPC_TIMEOUT=18000000

vllm serve deepseek-ai/DeepSeek-V3.2-Exp \
  --tensor-parallel-size 8 \
  --max-num-batched-tokens 32768 \
  --trust-remote-code \
  --kv-cache-dtype bfloat16 \
  --block-size 1

Accuracy Benchmarking

lm-eval --model local-completions --tasks gsm8k \
  --model_args model=deepseek-ai/DeepSeek-V3.2-Exp,base_url=http://127.0.0.1:8000/v1/completions,num_concurrent=100,max_retries=3,tokenized_requests=False

Reported GSM8K score: 0.9591 (5-shot) and 0.9538 (20-shot).

Performance Tips

  1. The kernels are mainly optimized for TP=1, so it is recommended to run this model under EP/DP mode (e.g. DP=8, EP=8, TP=1). If you hit any errors or hangs, try tensor parallel instead. Simple TP works and is more robust, but the performance is not optimal.
  2. The default config uses a custom fp8 KV cache. You can also use bfloat16 KV cache by specifying kv_cache_dtype=bfloat16. FP8 allows more tokens to be cached but incurs quantization/dequantization overhead. Use bfloat16 for short requests and fp8 for long requests.

Troubleshooting

  • CUDA error (flashmla-src/csrc/smxx/mla_combine.cu:201): invalid configuration argument: This may be caused by too large a batch size. Try --max-num-seqs 256 or smaller (default is 1024).
  • For thinking-mode toggling, refer to the DeepSeek-V3.1 recipe (deepseek-ai/DeepSeek-V3.1).

References