From f81f9a3c89e63f846c17930318b28324f5ba471d Mon Sep 17 00:00:00 2001
From: shaopeng-666 <lishaopeng21@huawei.com>
Date: Fri, 17 Apr 2026 22:54:21 +0800
Subject: [PATCH] [Doc] Add Qwen3.5 fused MC2 known issue for 0.18.0 release
 (#8378)
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---------

Signed-off-by: 李少鹏 <lishaopeng21@huawei.com>
---
 docs/source/tutorials/models/Qwen3.5-397B-A17B.md | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/docs/source/tutorials/models/Qwen3.5-397B-A17B.md b/docs/source/tutorials/models/Qwen3.5-397B-A17B.md
index 8204bcb3..c70ff358 100644
--- a/docs/source/tutorials/models/Qwen3.5-397B-A17B.md
+++ b/docs/source/tutorials/models/Qwen3.5-397B-A17B.md
@@ -599,3 +599,8 @@ vllm bench serve --model Eco-Tech/Qwen3.5-397B-A17B-w8a8-mtp --dataset-name rand
 ```
 
 After about several minutes, you can get the performance evaluation result.
+
+## Qwen3.5-397B-A17B Known issues
+
+- Issue1: For single-node deployment scenario, when fused_mc2 is enabled, using multi-DP model deployment may cause garbled or empty outputs after the model triggers recomputation.When tuning performance by adjusting model parallelism, ensure that this fused operator is disabled when DP > 1. For PD deployment scenario，D nodes can avoid this problem by enabling the recompute scheduler.
+  
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