vLLM reuses its inference kernels in the training forward pass for matching results
Overview
vLLM says its training forward pass now calls its inference kernels directly.
The stated aim is that the same token gets the same result across validated batch sizes, phases and parallel layouts. The kernels aligned are FP8 GEMM, sparse-attention Top-K, FP8 KV-cache reads, MoE communication and CUDA Graph execution.
The backward pass does not share these kernels. vLLM says it uses separate checks for the backward pass.
Written by AI from the articles below · updated Oct 15, 10:57 AM ET
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vLLM@vllm_projectOfficialvLLM training forward pass reuses its inference kernels for matching resultsAIvLLM says its training forward pass calls its inference kernels directly, aligning FP8 GEMM, sparse-attention Top-K, FP8 KV-cache reads, MoE communication and CUDA Graph execution. The aim is for the same token to get the same result across validated batch sizes, phases and parallel layouts. The backward pass uses separate checks.

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