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Flash Attention Speedup

Makes transformer attention faster and less memory-hungry on NVIDIA GPUs

Stars
14,195
Licence
MIT
Files
3 files

What it does

When installed, the agent knows how to switch a transformer model's attention computation to Flash Attention, a memory-efficient method that processes attention in chunks instead of building huge intermediate matrices. The skill walks the agent through checking the PyTorch version, enabling the built-in fast attention path, benchmarking the speedup, and checking that outputs still match the standard version. It also covers the separate flash-attn library for features like multi-query attention, sliding windows and H100 FP8.

Great for

  • Engineers training or running transformer models on long sequences that hit GPU memory limits
  • Developers who want faster inference on NVIDIA GPUs without changing model accuracy
  • Teams profiling attention performance before and after an optimization

Skip it if

  • Users without an NVIDIA GPU, since the examples require CUDA and the speedups do not apply to CPU-only setups
  • Anyone expecting the quoted 2-4x speedup and 10-20x memory reduction as guaranteed; these are general claims and results depend on hardware and sequence length
  • Production systems changed without testing, since the skill itself says to verify accuracy against a baseline

Try asking

  • “Make my PyTorch transformer use Flash Attention and check that the outputs still match the original”
  • “My training runs out of GPU memory on 4096-token sequences; help me enable an efficient attention backend”
  • “Benchmark standard attention against Flash Attention on my GPU and report the speedup”
  • “Set up sliding window attention with flash-attn for a long-context model”
Step-by-step guide: how to use Flash Attention SpeedupInstall, first run, examples, tips and FAQs

Install in 3 steps

  1. 1

    Download the skill

    The ZIP contains the 3 original files, the MIT licence and an attribution note.

    flash-attention.zip
  2. 2

    Add it to your agent

    Claude Code (all projects)

    mkdir -p ~/.claude/skills && unzip flash-attention.zip -d ~/.claude/skills/

    Claude Code / Agent SDK (this project only)

    mkdir -p .claude/skills && unzip flash-attention.zip -d .claude/skills/

    Claude apps (web/desktop): Settings → Capabilities → Skills → Upload skill, and choose the ZIP.

  3. 3

    Ask for the task

    No special command needed — the agent reads the skill's description and loads it when your request matches. Try one of the prompts above.

Get better results

  • Verify the speedup and accuracy on your own hardware and input sizes before relying on it, since the quoted figures are general claims
  • Install flash-attn in a dedicated environment, because it compiles CUDA code during installation and can fail on mismatched toolchains
  • Review any pip install or benchmark commands the agent proposes before running them, since they execute on your machine

What's inside

  • references/benchmarks.md
  • references/transformers-integration.md
  • SKILL.md

Redistributed unmodified from Orchestra-Research/AI-Research-SKILLs under the MIT licence. The assessment was drafted with AI from the skill's files on 2026-10-29. Skills can instruct your agent to run code — read SKILL.md and any scripts before installing.