6ee7f5cf71
### What this PR does / why we need it? Backport: https://github.com/vllm-project/vllm-ascend/pull/252 This support speculative decoding in Ascend, including speculating with a draft model、by matching n-grams in the prompt、using MLP speculators and using EAGLE based draft models. Backport: https://github.com/vllm-project/vllm-ascend/pull/423 spec decode MultiStepWorker support TP1DraftModelRunner fully, support run the draft_model_runner with multi-step prepare on the NPU directly and support draft_model_runner use MLA. 1. before this pr, `MultiStepWorker` would not step into the branch using NPU prepare, but only into the branch using CPU prepare (`line 52` of `vllm_ascend/patch/patch_multi_step_worker.py`). Although this has `no effect` on the `correct operation` of speculative decoding and the performance of the two branches is basically the same as of the current version, I support entering this branch in this PR. In general, there are two main changes in `patch_multi_step_worker.py`: first, the `is_cuda_like()` check is removed and the `TP1DraftModelRunner` rewritten in vllm_ascend is used; second, the `supports_gpu_multi_step()` function is made to return true on NPU devices when outer Multi_step_worker could work correct. 3. before this pr, `TP1DraftModelRunner` only supports Attention on NPU, but not MLA. The relevant adaptation is in `vllm_ascend/worker/draft_model_runner.py`. Although I don’t know why the `input_positions` of `model_input.attn_metadata` in vllm-ascend needs to be added in `execute_model`, it is done in `model_runner.py`, so I also made corresponding changes. Otherwise, when atten_backend is MLA, it will prompt that input_positions cannot be found. 4. I commented out two lines in `draft_model_runner.py` in `line118` to support the scenario of K>1. ``` # lora_mapping=model_input.lora_mapping, # lora_requests=model_input.lora_requests, ``` I added comments. In the future, when vllm-ascend supports lora feature, the changes here can be restored. TODO： - [ ] revert the patch when the related issues are addressed in vllm ### How was this patch tested? CI passed with new added test. - e2e test for medusa proposer: tests/singlecard/spec_decode/e2e/test_medusa_correctness.py - e2e test for mlp proposer: tests/singlecard/spec_decode/e2e/test_mlp_correctness.py - e2e test for n-gram proposer: tests/singlecard/spec_decode/e2e/test_ngram_correctness.py Tests for patched files: - tests/singlecard/spec_decode/test_dynamic_spec_decode.py - tests/singlecard/spec_decode/test_multi_step_worker.py - tests/singlecard/spec_decode/test_ngram_worker.py - tests/singlecard/spec_decode/test_spec_decode_worker.py --------- Signed-off-by: MengqingCao <cmq0113@163.com> Co-authored-by: mengwei805 <mengwei25@huawei.com>
vLLM Ascend Plugin
| About Ascend | Documentation | #sig-ascend | Users Forum | Weekly Meeting |
English | 中文
Latest News 🔥
- [2025/03] We hosted the vLLM Beijing Meetup with vLLM team! Please find the meetup slides here.
- [2025/02] vLLM community officially created vllm-project/vllm-ascend repo for running vLLM seamlessly on the Ascend NPU.
- [2024/12] We are working with the vLLM community to support [RFC]: Hardware pluggable.
Overview
vLLM Ascend (vllm-ascend) is a community maintained hardware plugin for running vLLM seamlessly on the Ascend NPU.
It is the recommended approach for supporting the Ascend backend within the vLLM community. It adheres to the principles outlined in the [RFC]: Hardware pluggable, providing a hardware-pluggable interface that decouples the integration of the Ascend NPU with vLLM.
By using vLLM Ascend plugin, popular open-source models, including Transformer-like, Mixture-of-Expert, Embedding, Multi-modal LLMs can run seamlessly on the Ascend NPU.
Prerequisites
- Hardware: Atlas 800I A2 Inference series, Atlas A2 Training series
- OS: Linux
- Software:
- Python >= 3.9
- CANN >= 8.0.0
- PyTorch >= 2.5.1, torch-npu >= 2.5.1.dev20250320
- vLLM (the same version as vllm-ascend)
Getting Started
Please refer to QuickStart and Installation for more details.
Contributing
See CONTRIBUTING for more details, which is a step-by-step guide to help you set up development environment, build and test.
We welcome and value any contributions and collaborations:
- Please let us know if you encounter a bug by filing an issue
- Please use User forum for usage questions and help.
Branch
vllm-ascend has main branch and dev branch.
- main: main branch，corresponds to the vLLM main branch, and is continuously monitored for quality through Ascend CI.
- vX.Y.Z-dev: development branch, created with part of new releases of vLLM. For example,
v0.7.3-devis the dev branch for vLLMv0.7.3version.
Below is maintained branches:
| Branch | Status | Note |
|---|---|---|
| main | Maintained | CI commitment for vLLM main branch |
| v0.7.1-dev | Unmaintained | Only doc fixed is allowed |
| v0.7.3-dev | Maintained | CI commitment for vLLM 0.7.3 version |
Please refer to Versioning policy for more details.
Weekly Meeting
- vLLM Ascend Weekly Meeting: https://tinyurl.com/vllm-ascend-meeting
- Wednesday, 15:00 - 16:00 (UTC+8, Convert to your timezone)
License
Apache License 2.0, as found in the LICENSE file.