---
id: pr-flashinfer-1681
repo: flashinfer-ai/flashinfer
pr: 1681
title: 'perf: improve performance of cutlass fmha'
author: yzh119
date: '2025-09-16'
url: https://github.com/flashinfer-ai/flashinfer/pull/1681
source_category: upstream-code
architectures:
- sm100
tags:
- tcgen05
- flash-attention
- attention
techniques:
- warp-specialization
- persistent-kernel
hardware_features:
- tcgen05
- tmem
- tma
kernel_types:
- flash-attention
- attention
- prefill
languages:
- cuda-cpp
captured_at: 2026-04-16
status: merged
merge_sha: 67c7e889605106778aac5cdd6d7feee0fccfc86f
inclusion_reason: manually curated, Blackwell kernel relevance
changed_paths:
- include/flashinfer/attention/blackwell/collective/fmha_fusion.hpp
- include/flashinfer/attention/blackwell/collective/sm100_fmha_fwd_mainloop_tma_warpspecialized.hpp
head_ref_oid: 2ddc34ce3f6030c076b0227325460091f57d27ef
artifact_dir: evidence/pull-bundles/flashinfer/gh-1681
---
# perf: improve performance of cutlass fmha

- Repository: `flashinfer-ai/flashinfer`
- PR: [1681](https://github.com/flashinfer-ai/flashinfer/pull/1681)
- Decision: `manually curated, Blackwell kernel relevance`
- Reason: manually curated, Blackwell kernel relevance

## Changed Paths

- `include/flashinfer/attention/blackwell/collective/fmha_fusion.hpp`
- `include/flashinfer/attention/blackwell/collective/sm100_fmha_fwd_mainloop_tma_warpspecialized.hpp`

## Evidence Bundle

`evidence/pull-bundles/flashinfer/gh-1681`
