sentinel集成dubbo的场景，超过一定流量后会出现流量大幅抖动

## Issue Description

Type: *bug report* or *feature request*

### Describe what happened (or what feature you want)

dubbo在集成了sentinel的场景下，测试发现，我用相同的流量发起请求，sentinel统计的流量会有大幅抖动。在某些特殊场景下可能会偶尔出现超过请求流量。查看代码发现sentinel集成到了dubbo的调用链中。尝试加大dubbo的线程池，发现并没有解决相关问题。这种情况有什么解决方案吗。

本地测试流量1500 限流2000，dubbo统计会波动，最低到600多

### Describe what you expected to happen

### How to reproduce it (as minimally and precisely as possible)

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### Tell us your environment

### Anything else we need to know?

Start by reproducing the Sentinel–Dubbo integration behavior described with 1,500 incoming traffic and a limit of 2,000, then trace the Sentinel integration in the Dubbo invocation chain. The issue provides no file, test, or environment details; done would require identifying why the recorded traffic fluctuates and documenting or validating a fix.

Written by the indexing model from the issue text.