zzhxxx dd8571860d [Feature] Support DSA-CP for Hybrid scenario (#5702)
Signed-off-by: zzhx1 <zzh_201018@outlook.com>

### What this PR does / why we need it?
> Extracted from PR #5513
Based on the Sharded-CP feature PR:#4702;
RFC:https://github.com/vllm-project/vllm/issues/30055

### Support FULL_DECODE_ONLY Mode under PD-Mixed Scenario:
Extends DSA-CP to handle the FULL_DECODE_ONLY execution mode when
running in a prefill-decode mixed (PD-mixed) serving environment,
improving throughput and resource utilization for decode-intensive
workloads.
**In pure prefill nodes:**
- Both q_proj and o_proj are sharded across world ranks, using
**broadcast** for weights distribution.

**In PD-mixed nodes (supporting both prefill and decode):**

- q_proj is fully replicated (not sharded) to avoid communication
overhead during decoding.
- o_proj Using the original TP `RowParallelLinear` method to store
weights

**During prefill execution:**
- o_proj forwards through all_gather to collect weights, reconstructing
the complete o_proj weights on each card.

**During decode (graph replay phase):**
- Additional all_to_all (before o_proj) and reduce_scatter (after
o_proj) are introduced to enable sequence-parallel output aggregation
while maintaining correctness under SFA CP.

### benchmark:
- TTFT increased by **527%**
- TPOT increased by **180%**

<img width="1550" height="938" alt="image"
src="https://github.com/user-attachments/assets/9b7a03d8-a3db-4a99-8923-6e5bfcfecf72"
/>


### Does this PR introduce _any_ user-facing change?
None
### How was this patch tested?

- vLLM version: v0.13.0
- vLLM main:
2f4e6548ef

---------

Signed-off-by: zzhx1 <zzh_201018@outlook.com>
Signed-off-by: zzhxx <zhangzihang23@mails.ucas.ac.cn>
Co-authored-by: clrs97 <524936896@qq.com>
2026-01-22 10:12:09 +08:00
2025-08-11 22:21:29 +08:00
2026-01-21 09:30:30 +08:00
2026-01-22 09:29:50 +08:00
2026-01-22 09:29:50 +08:00
2025-02-05 10:53:12 +08:00
2026-01-22 09:29:50 +08:00
2026-01-12 11:21:31 +08:00
2025-01-29 02:44:13 -08:00
2025-12-20 17:03:25 +08:00
2025-12-01 09:09:51 +08:00

vllm-ascend

vLLM Ascend Plugin

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Latest News 🔥

  • [2025/12] We released the new official version v0.11.0! Please follow the official guide to start using vLLM Ascend Plugin on Ascend.
  • [2025/09] We released the new official version v0.9.1! Please follow the official guide to start deploy large scale Expert Parallelism (EP) on Ascend.
  • [2025/08] We hosted the vLLM Beijing Meetup with vLLM and Tencent! Please find the meetup slides here.
  • [2025/06] User stories page is now live! It kicks off with LLaMA-Factory/verl//TRL/GPUStack to demonstrate how vLLM Ascend assists Ascend users in enhancing their experience across fine-tuning, evaluation, reinforcement learning (RL), and deployment scenarios.
  • [2025/06] Contributors page is now live! All contributions deserve to be recorded, thanks for all contributors.
  • [2025/05] We've released first official version v0.7.3! We collaborated with the vLLM community to publish a blog post sharing our practice: Introducing vLLM Hardware Plugin, Best Practice from Ascend NPU.
  • [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, Atlas 800I A3 Inference series, Atlas A3 Training series, Atlas 300I Duo (Experimental)
  • OS: Linux
  • Software:
    • Python >= 3.10, < 3.12
    • CANN == 8.3.rc2 (Ascend HDK version refers to here)
    • PyTorch == 2.8.0, torch-npu == 2.8.0
    • vLLM (the same version as vllm-ascend)

Getting Started

Please use the following recommended versions to get started quickly:

Version Release type Doc
v0.13.0rc1 Latest release candidate QuickStart and Installation for more details
v0.11.0 Latest stable version 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:

Branch

vllm-ascend has main branch and dev branch.

  • main: main branchcorresponds to the vLLM main branch, and is continuously monitored for quality through Ascend CI.
  • releases/vX.Y.Z: development branch, created with part of new releases of vLLM. For example, releases/v0.13.0 is the dev branch for vLLM v0.13.0 version.

Below is maintained branches:

Branch Status Note
main Maintained CI commitment for vLLM main branch and vLLM v0.13.0 tag
v0.7.1-dev Unmaintained Only doc fixed is allowed
v0.7.3-dev Maintained CI commitment for vLLM 0.7.3 version, only bug fix is allowed and no new release tag any more.
v0.9.1-dev Maintained CI commitment for vLLM 0.9.1 version
v0.11.0-dev Maintained CI commitment for vLLM 0.11.0 version
releases/v0.13.0 Maintained CI commitment for vLLM 0.13.0 version
rfc/feature-name Maintained Feature branches for collaboration

Please refer to Versioning policy for more details.

Weekly Meeting

License

Apache License 2.0, as found in the LICENSE file.

Description
XC-LLM: A Specially Optimized LLM Inference Engine for ModelHub XC
Readme Apache-2.0 31 MiB
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