sglang/docs/backend/attention_backend.md

Attention Backend

Supporting matrix for different attention backends

Backend	Page Size > 1	Spec Decoding	MLA	Sliding Window	MultiModal
FlashInfer	✅	✅	✅	✅	✅
FA3	✅	✅	✅	✅	✅
Triton	❌	✅	✅	❌	❌
Torch Native	❌	❌	❌	❌	❌

User guide

Launch command for different attention backends.

• FlashInfer (Default for Non-Hopper Machines, e.g., A100, A40)

python3 -m sglang.launch_server --model meta-llama/Meta-Llama-3.1-8B-Instruct --attention-backend flashinfer
python3 -m sglang.launch_server --tp 8 --model deepseek-ai/DeepSeek-V3 --attention-backend flashinfer --trust-remote-code

• FlashAttention 3 (Default for Hopper Machines, e.g., H100, H200, H20)

python3 -m sglang.launch_server --model meta-llama/Meta-Llama-3.1-8B-Instruct --attention-backend fa3
python3 -m sglang.launch_server --tp 8 --model deepseek-ai/DeepSeek-V3 --trust-remote-code --attention-backend fa3

• Triton

python3 -m sglang.launch_server --model meta-llama/Meta-Llama-3.1-8B-Instruct --attention-backend triton
python3 -m sglang.launch_server --tp 8 --model deepseek-ai/DeepSeek-V3 --attention-backend triton --trust-remote-code

• Torch Native

python3 -m sglang.launch_server --model meta-llama/Meta-Llama-3.1-8B-Instruct --attention-backend torch_native