Block Sparse Flash Attention

Name: Block Sparse Flash Attention
Uploaded: 2026-10-03T06:37:00.300373+00:00
Duration: 441 s
Description: Block Sparse FlashAttention (BSFA) accelerates long-context prefill inference by computing exact query-key scores first, then selectively processing value blocks based on their importance. It addresses the quadratic complexity bottleneck of standard attention by skipping low-scoring value blocks, achieving up to 1.24x speedup on reasoning tasks while maintaining high accuracy.

Block Sparse FlashAttention (BSFA) accelerates long-context prefill inference by computing exact query-key scores first, then selectively processing value blocks based on their importance. It addresses the quadratic complexity bottleneck of standard attention by skipping low-scoring value blocks, achieving up to 1.24x speedup on reasoning tasks while maintaining high accuracy.

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