---
id: pr-sglang-23148
repo: sgl-project/sglang
pr: 23148
title: '[codex] diffusion: enable group norm silu fuse by default'
author: BBuf
date: '2026-05-02'
url: https://github.com/sgl-project/sglang/pull/23148
source_category: upstream-code
architectures:
- sm100
tags:
- CUDA kernel
- compiler_runtime
- fused norm
- jit_kernel
- norm_elementwise
- triton kernel
techniques:
- kernel-fusion
hardware_features: []
kernel_types:
- compiler
- norm
languages:
- cuda-cpp
- triton
captured_at: '2026-05-16'
status: merged
merge_sha: b712dd48feb8acb7c4214d646766c226a656d304
inclusion_reason: Look for fusion, vectorization, dtype conversion, and store-traffic reductions before changing math.
changed_paths:
- python/sglang/jit_kernel/diffusion/group_norm_silu.py
- python/sglang/jit_kernel/diffusion/triton/group_norm_silu.py
- python/sglang/jit_kernel/tests/diffusion/test_group_norm_silu.py
- python/sglang/multimodal_gen/envs.py
- python/sglang/multimodal_gen/runtime/models/vaes/hunyuanvae.py
artifact_dir: evidence/pull-bundles/sglang/gh-23148
head_ref_oid: d8ce3c1d461f7da3d4a6cfb65cbc9421629df18b
---
# [codex] diffusion: enable group norm silu fuse by default

- Repository: `sgl-project/sglang`
- PR: [23148](https://github.com/sgl-project/sglang/pull/23148)
- Decision: `Look for fusion, vectorization, dtype conversion, and store-traffic reductions before changing math.`
- Reason: Look for fusion, vectorization, dtype conversion, and store-traffic reductions before changing math.

## Changed Paths

- `python/sglang/jit_kernel/diffusion/group_norm_silu.py`
- `python/sglang/jit_kernel/diffusion/triton/group_norm_silu.py`
- `python/sglang/jit_kernel/tests/diffusion/test_group_norm_silu.py`
- `python/sglang/multimodal_gen/envs.py`
- `python/sglang/multimodal_gen/runtime/models/vaes/hunyuanvae.py`

## Evidence Bundle

`evidence/pull-bundles/sglang/gh-23148`
