Exceeded limit on max bytes to buffer : 262144

## 1.场景
同步HR的人员数据到ucenter系统。流程HR-->PO-->网关-->ucenter系统。
## 2.问题
HR系统的一次全量数据，约7m。请求流程到网关的时候，报错如下
```
2024-01-23 10:12:29 [shenyu-netty-epoll-5] ERROR org.apache.shenyu.web.handler.GlobalErrorHandler:53 - traceId: 4b7e8759-b47f-416b-8aec-02213566bf78,GUID: ,DSystem: EMS,SSystem: CCS  handle error: [22a982c6-660] Resolved [DataBufferLimitException: Exceeded limit on max bytes to buffer : 262144] for HTTP POST /ucenter/sync/receiveDeptsInfo

org.springframework.core.io.buffer.DataBufferLimitException: Exceeded limit on max bytes to buffer : 262144

at org.springframework.core.io.buffer.LimitedDataBufferList.raiseLimitException(LimitedDataBufferList.java:99)

Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException:

Error has been observed at the following site(s):

*__checkpoint ⇢ com.techlex.gateway.filter.TraceInfoFilter [DefaultWebFilterChain]

*__checkpoint ⇢ org.apache.shenyu.web.filter.FileSizeFilter [DefaultWebFilterChain]

*__checkpoint ⇢ com.techlex.gateway.filter.HealthFilter [DefaultWebFilterChain]

*__checkpoint ⇢ org.apache.shenyu.web.filter.CrossFilter [DefaultWebFilterChain]

*__checkpoint ⇢ org.apache.shenyu.web.filter.LocalDispatcherFilter [DefaultWebFilterChain]

*__checkpoint ⇢ org.springframework.boot.actuate.metrics.web.reactive.server.MetricsWebFilter [DefaultWebFilterChain]

*__checkpoint ⇢ HTTP POST "/ucenter/sync/receiveDeptsInfo" [ExceptionHandlingWebHandler]
```
## 3.找错
报错的信息很明显
```
org.springframework.core.io.buffer.DataBufferLimitException: Exceeded limit on max bytes to buffer : 262144
```
spring的core包中DataBufferLimit报错了，定位到源码处
![](/media/202401/2024-01-23_172632_389647.png)
## 4.解决
通过查看源码可知，

![](/media/202401/2024-01-23_175246_330107.png)

![](/media/202401/2024-01-23_175340_684038.png)

![](/media/202401/2024-01-23_175515_655815.png)

![](/media/202401/2024-01-23_175836_208630.png)

![](/media/202401/2024-01-23_180144_490360.png)

由此可见，spring官方设置了默认值。
由源码可知，存在设置maxInMemorySize的方法，如下
```
	public void setMaxInMemorySize(int byteCount) {
		this.maxInMemorySize = byteCount;
	}
```
因此有办法可以从外部设置好值传给这个类。
由于时间原因，我这里采取一个取巧的方法，重写这个类，重新设值，如下
![](/media/202401/2024-01-23_180932_148378.png)
## 5.验证
![](/media/202401/2024-01-23_181202_499266.png)
自此，解决了该问题。