---
id: pr-vllm-34434
repo: vllm-project/vllm
pr: 34434
title: '[CPU][Perf] Accelerate Attention head for s390x using vector intrinsics'
author: R3hankhan123
date: '2026-02-24'
url: https://github.com/vllm-project/vllm/pull/34434
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: 34ce0ffd1f3c7b5e2bcc6073dd1525f266133755
inclusion_reason: kernel file changes
changed_paths:
- csrc/cpu/cpu_attn.cpp
- csrc/cpu/cpu_attn_impl.hpp
- csrc/cpu/cpu_attn_vxe.hpp
- csrc/cpu/generate_cpu_attn_dispatch.py
- vllm/engine/arg_utils.py
- vllm/v1/attention/backends/cpu_attn.py
head_ref_oid: a6c9653d16a2b7e424544e8827a93596e659eed9
artifact_dir: evidence/pull-bundles/vllm/gh-34434
---
# [CPU][Perf] Accelerate Attention head for s390x using vector intrinsics

- Repository: `vllm-project/vllm`
- PR: [34434](https://github.com/vllm-project/vllm/pull/34434)
- Decision: `kernel file changes`
- Reason: kernel file changes

## Changed Paths

- `csrc/cpu/cpu_attn.cpp`
- `csrc/cpu/cpu_attn_impl.hpp`
- `csrc/cpu/cpu_attn_vxe.hpp`
- `csrc/cpu/generate_cpu_attn_dispatch.py`
- `vllm/engine/arg_utils.py`
- `vllm/v1/attention/backends/cpu_attn.py`

## Evidence Bundle

`evidence/pull-bundles/vllm/gh-34434`
