---
id: pr-flashinfer-3227
repo: flashinfer-ai/flashinfer
pr: 3227
title: '[Bugfix] Fix fused MoE autotuning correctness issues by filtering clusterDimZ'
author: wzhao18
date: '2026-05-06'
url: https://github.com/flashinfer-ai/flashinfer/pull/3227
source_category: upstream-code
architectures:
- sm100
tags:
- arch_pipeline
- attention_kv
- fp4
- fp8
- fused moe
- gemm_quant
- moe_routing
- sampling
- scheduler_autotune
- topk
techniques:
- autotuning
- fine-grained-quantization
- kernel-fusion
- pipeline-stages
- tile-scheduling
hardware_features:
- fp4
- fp8
kernel_types:
- attention
- gemm
- moe
- runtime
- sampling
- scheduler
languages:
- cuda-cpp
captured_at: '2026-05-16'
status: merged
merge_sha: 2bb1f857f0467f47b7ed5c0fc2e104a710ae89fa
inclusion_reason: Separate routing, permutation, top-k, and expert GEMM costs; keep tail-token and expert-layout tests attached to the idea.
changed_paths:
- csrc/trtllm_batched_gemm_runner.cu
- flashinfer/fused_moe/core.py
- tests/moe/test_trtllm_gen_moe_autotune_tactics.py
artifact_dir: evidence/pull-bundles/flashinfer/gh-3227
head_ref_oid: 25fd9a13e5adafeebb7790748b3137ce20f668b9
---
# [Bugfix] Fix fused MoE autotuning correctness issues by filtering clusterDimZ

- Repository: `flashinfer-ai/flashinfer`
- PR: [3227](https://github.com/flashinfer-ai/flashinfer/pull/3227)
- Decision: `Separate routing, permutation, top-k, and expert GEMM costs; keep tail-token and expert-layout tests attached to the idea.`
- Reason: Separate routing, permutation, top-k, and expert GEMM costs; keep tail-token and expert-layout tests attached to the idea.

## Changed Paths

- `csrc/trtllm_batched_gemm_runner.cu`
- `flashinfer/fused_moe/core.py`
- `tests/moe/test_trtllm_gen_moe_autotune_tactics.py`

## Evidence Bundle

`evidence/pull-bundles/flashinfer/gh-3227`
