@vllm_project
π Day-0 support for @deepseek_ai V4 Pro and Flash on vLLM β a new generation of DeepSeek model, purpose-built for tasks up to 1M tokens. Alongside the release, we're publishing a first-principles walkthrough of the new long-context attention and how we implemented it in vLLM. The new attention mechanism, in four moves: β’ Shared K/V + inverse RoPE β 2Γ memory savings β’ c4a / c128a KV compression β 4Γβ128Γ savings β’ DeepSeek Sparse Attention over compressed tokens β’ Short sliding window for locality across compression boundaries At 1M context, per-layer KV state is ~8.7Γ smaller than a DeepSeek V3.2-style 61-layer stack (9.62 GiB vs 83.9 GiB, bf16). fp8 attention cache + fp4 indexer cache shrink it further. vLLM side: β’ Unified hybrid KV cache β single logical block size (256 native positions) across all compression rates; compressor state folded into the SWA KV cache spec so prefix caching, disagg prefill, CUDA graphs and MTP reuse the same abstraction β’ Three page-size buckets for the full 5-way cache stack β no cross-kind fragmentation β’ Fused kernels: compressor + RMSNorm + RoPE + cache insert (1.4β3Γ), inverse RoPE + fp8 quant (2β3Γ), Q-norm + KV RoPE + K insert (10β20Γ) β’ Multi-stream overlap of indexer vs main-KV compression vs SWA insertion Disaggregated serving is supported out of the box and strongly recommended for best performance. Follow our recipes site for verified commands for @nvidia Blackwell (B200, B300, GB200, GB300) and Hopper (H100/H200/H20) systems. Thanks to the @deepseek_ai team for open-sourcing DeepSeek V4, and to @inferact for landing day-0 support π€ π Blog: https://t.co/Eh7vk6xVJy π Recipes: https://t.co/jlWuzYyZeX π€ https://t.co/IA9qAysqJk