---
id: pr-vllm-29627
repo: vllm-project/vllm
pr: 29627
title: '[Attention] Cache attention metadata builds across hybrid KV-cache groups'
author: LucasWilkinson
date: '2025-12-16'
url: https://github.com/vllm-project/vllm/pull/29627
source_category: upstream-code
architectures:
- sm100
tags:
- attention
techniques: []
hardware_features: []
kernel_types:
- attention
languages:
- python
captured_at: '2026-04-27'
status: merged
merge_sha: 9fec0e13d512b6b9082e40297582d8052f434610
inclusion_reason: kernel file changes
changed_paths:
- tests/v1/attention/test_chunked_local_attention.py
- vllm/attention/layers/chunked_local_attention.py
- vllm/envs.py
- vllm/v1/attention/backends/flash_attn.py
- vllm/v1/attention/backends/mamba2_attn.py
- vllm/v1/attention/backends/utils.py
- vllm/v1/worker/gpu_model_runner.py
head_ref_oid: e37e7c6d8233be1dff46408b32803a408f97034b
artifact_dir: evidence/pull-bundles/vllm/gh-29627
---
# [Attention] Cache attention metadata builds across hybrid KV-cache groups

- Repository: `vllm-project/vllm`
- PR: [29627](https://github.com/vllm-project/vllm/pull/29627)
- Decision: `kernel file changes`
- Reason: kernel file changes

## Changed Paths

- `tests/v1/attention/test_chunked_local_attention.py`
- `vllm/attention/layers/chunked_local_attention.py`
- `vllm/envs.py`
- `vllm/v1/attention/backends/flash_attn.py`
- `vllm/v1/attention/backends/mamba2_attn.py`
- `vllm/v1/attention/backends/utils.py`
- `vllm/v1/worker/gpu_model_runner.py`

## Evidence Bundle

`evidence/pull-bundles/vllm/gh-29627`
