---
id: pr-vllm-36540
repo: vllm-project/vllm
pr: 36540
title: '[fix] Remove trtllm ragged mla prefills'
author: evezhier
date: '2026-03-31'
url: https://github.com/vllm-project/vllm/pull/36540
source_category: upstream-code
architectures:
- sm100
tags:
- attention_kv
- benchmark_test
- csrc kernel
techniques: []
hardware_features: []
kernel_types:
- attention
- mla
languages:
- cuda-cpp
- triton
captured_at: '2026-05-16'
status: merged
merge_sha: 598190aac38a42d8c51ea46a3061e46d9078b3a5
inclusion_reason: Preserve page/KV/layout and plan-run contracts; profile memory traffic separately from math utilization.
changed_paths:
- csrc/attention/merge_attn_states.cu
- csrc/ops.h
- csrc/torch_bindings.cpp
- tests/kernels/attention/test_merge_attn_states.py
- vllm/_custom_ops.py
- vllm/model_executor/layers/attention/mla_attention.py
- vllm/v1/attention/ops/merge_attn_states.py
- vllm/v1/attention/ops/triton_merge_attn_states.py
artifact_dir: evidence/pull-bundles/vllm/gh-36540
head_ref_oid: c3f0df16de2864c55055301627e8256a96001545
---
# [fix] Remove trtllm ragged mla prefills

- Repository: `vllm-project/vllm`
- PR: [36540](https://github.com/vllm-project/vllm/pull/36540)
- Decision: `Preserve page/KV/layout and plan-run contracts; profile memory traffic separately from math utilization.`
- Reason: Preserve page/KV/layout and plan-run contracts; profile memory traffic separately from math utilization.

## Changed Paths

- `csrc/attention/merge_attn_states.cu`
- `csrc/ops.h`
- `csrc/torch_bindings.cpp`
- `tests/kernels/attention/test_merge_attn_states.py`
- `vllm/_custom_ops.py`
- `vllm/model_executor/layers/attention/mla_attention.py`
- `vllm/v1/attention/ops/merge_attn_states.py`
- `vllm/v1/attention/ops/triton_merge_attn_states.py`

## Evidence Bundle

`evidence/pull-bundles/vllm/gh-36540`
