---
id: pr-sglang-4932
repo: sgl-project/sglang
pr: 4932
title: '[Fix] avoid stream sync and torch compile in prefill for fa3 backend'
author: Fridge003
date: '2025-03-30'
url: https://github.com/sgl-project/sglang/pull/4932
source_category: upstream-code
architectures:
- sm100
tags: []
techniques: []
hardware_features: []
kernel_types: []
languages: []
captured_at: '2026-05-16'
status: merged
merge_sha: e62d60fe6d7ce656e9338284d08fc97917a1c70e
inclusion_reason: defer
changed_paths:
- python/sglang/srt/layers/attention/flashattention_backend.py
- python/sglang/srt/layers/attention/flashinfer_mla_backend.py
- python/sglang/srt/layers/attention/flashmla_backend.py
- python/sglang/srt/managers/schedule_batch.py
- python/sglang/srt/model_executor/cuda_graph_runner.py
- python/sglang/srt/model_executor/forward_batch_info.py
- python/sglang/srt/speculative/eagle_draft_cuda_graph_runner.py
artifact_dir: evidence/pull-bundles/sglang/gh-4932
head_ref_oid: 6837911ea0f87cb56a8fa4ee09349fce2fec5e00
---
# [Fix] avoid stream sync and torch compile in prefill for fa3 backend

- Repository: `sgl-project/sglang`
- PR: [4932](https://github.com/sgl-project/sglang/pull/4932)
- Decision: `defer`
- Reason: defer

## Changed Paths

- `python/sglang/srt/layers/attention/flashattention_backend.py`
- `python/sglang/srt/layers/attention/flashinfer_mla_backend.py`
- `python/sglang/srt/layers/attention/flashmla_backend.py`
- `python/sglang/srt/managers/schedule_batch.py`
- `python/sglang/srt/model_executor/cuda_graph_runner.py`
- `python/sglang/srt/model_executor/forward_batch_info.py`
- `python/sglang/srt/speculative/eagle_draft_cuda_graph_runner.py`

## Evidence Bundle

`evidence/pull-bundles/sglang/gh-4932`
