---
id: pr-cccl-cub-8284
repo: NVIDIA/cccl
pr: 8284
title: Expose `max_segment_size` guarantee in cuda.compute
author: shwina
date: '2026-04-06'
url: https://github.com/NVIDIA/cccl/pull/8284
source_category: upstream-code
architectures:
- sm100
tags:
- benchmark
- benchmark_test
- block reduce
- cuda.compute
- memory_primitives
- radix sort
- reduce
- segmented reduce
techniques: []
hardware_features: []
kernel_types:
- memory
- sort
languages:
- cuda-cpp
captured_at: '2026-05-16'
status: merged
merge_sha: 00073bbec0a3e91830c5800e5b88cf4caab3d4c3
inclusion_reason: Mine shape sets, tolerance rules, warmup logic, and profile commands before mutating code.
changed_paths:
- c/parallel/include/cccl/c/segmented_reduce.h
- c/parallel/src/segmented_reduce.cu
- c/parallel/test/test_segmented_reduce.cpp
- python/cuda_cccl/benchmarks/compute/quick_configs.yaml
- python/cuda_cccl/benchmarks/compute/run_benchmarks.py
- python/cuda_cccl/benchmarks/compute/segmented_reduce/variable_sum.py
- python/cuda_cccl/cuda/compute/_bindings.pyi
- python/cuda_cccl/cuda/compute/_bindings_impl.pyx
- python/cuda_cccl/cuda/compute/algorithms/_segmented_reduce.py
- python/cuda_cccl/tests/compute/test_segmented_reduce.py
artifact_dir: evidence/pull-bundles/cccl-cub/gh-8284
head_ref_oid: 3112e7754c6bd8e617782a314a4e9358c0d32e09
---
# Expose `max_segment_size` guarantee in cuda.compute

- Repository: `NVIDIA/cccl`
- PR: [8284](https://github.com/NVIDIA/cccl/pull/8284)
- Decision: `Mine shape sets, tolerance rules, warmup logic, and profile commands before mutating code.`
- Reason: Mine shape sets, tolerance rules, warmup logic, and profile commands before mutating code.

## Changed Paths

- `c/parallel/include/cccl/c/segmented_reduce.h`
- `c/parallel/src/segmented_reduce.cu`
- `c/parallel/test/test_segmented_reduce.cpp`
- `python/cuda_cccl/benchmarks/compute/quick_configs.yaml`
- `python/cuda_cccl/benchmarks/compute/run_benchmarks.py`
- `python/cuda_cccl/benchmarks/compute/segmented_reduce/variable_sum.py`
- `python/cuda_cccl/cuda/compute/_bindings.pyi`
- `python/cuda_cccl/cuda/compute/_bindings_impl.pyx`
- `python/cuda_cccl/cuda/compute/algorithms/_segmented_reduce.py`
- `python/cuda_cccl/tests/compute/test_segmented_reduce.py`

## Evidence Bundle

`evidence/pull-bundles/cccl-cub/gh-8284`
