---
id: pr-tensorrt-llm-11899
repo: NVIDIA/TensorRT-LLM
pr: 11899
title: '[TRTLLM-10421][perf] Add fused cat+fp8_quantize CUDA kernel for DSA indexer'
author: kaiyux
date: '2026-03-10'
url: https://github.com/NVIDIA/TensorRT-LLM/pull/11899
source_category: upstream-code
architectures:
- sm100
tags:
- DSA
- benchmark_test
- gemm_quant
techniques:
- fine-grained-quantization
- kernel-fusion
hardware_features:
- fp8
kernel_types:
- attention
- gemm
languages:
- cuda-cpp
captured_at: '2026-05-16'
status: merged
merge_sha: 9a070ed709f3e8008a24efdc3dbbfc852b1bfc9a
inclusion_reason: Inspect scale layout, accumulator type, tile/schedule choice, epilogue fusion, and partial-tile guards before deriving a candidate.
changed_paths:
- cpp/tensorrt_llm/kernels/fusedCatFp8.cu
- cpp/tensorrt_llm/kernels/fusedCatFp8.h
- cpp/tensorrt_llm/thop/CMakeLists.txt
- cpp/tensorrt_llm/thop/fusedCatFp8Op.cpp
- tensorrt_llm/_torch/attention_backend/sparse/dsa.py
- tensorrt_llm/_torch/custom_ops/cpp_custom_ops.py
- tests/unittest/_torch/thop/serial/test_fused_cat_fp8.py
artifact_dir: evidence/pull-bundles/tensorrt-llm/gh-11899
head_ref_oid: 3d3f4febf8b1e3e917a0b1ed092695ccce1adbf1
---
# [TRTLLM-10421][perf] Add fused cat+fp8_quantize CUDA kernel for DSA indexer

- Repository: `NVIDIA/TensorRT-LLM`
- PR: [11899](https://github.com/NVIDIA/TensorRT-LLM/pull/11899)
- Decision: `Inspect scale layout, accumulator type, tile/schedule choice, epilogue fusion, and partial-tile guards before deriving a candidate.`
- Reason: Inspect scale layout, accumulator type, tile/schedule choice, epilogue fusion, and partial-tile guards before deriving a candidate.

## Changed Paths

- `cpp/tensorrt_llm/kernels/fusedCatFp8.cu`
- `cpp/tensorrt_llm/kernels/fusedCatFp8.h`
- `cpp/tensorrt_llm/thop/CMakeLists.txt`
- `cpp/tensorrt_llm/thop/fusedCatFp8Op.cpp`
- `tensorrt_llm/_torch/attention_backend/sparse/dsa.py`
- `tensorrt_llm/_torch/custom_ops/cpp_custom_ops.py`
- `tests/unittest/_torch/thop/serial/test_fused_cat_fp8.py`

## Evidence Bundle

`evidence/pull-bundles/tensorrt-llm/gh-11899`
