由于近期线上单量暴涨，第三方反馈部分工单业务存在查询处理失败现象，经排查是当前系统通过FeignClient调用下游系统出现部分超时失败（异常代码贴在下方）。
Caused by: feign.RetryableException: Read timed out executing POST http://xxxx
at feign.FeignException.errorExecuting(FeignException.java:84) ~[feign-core-10.1.0.jar!/:na]
at feign.SynchronousMethodHandler.executeAndDecode(SynchronousMethodHandler.java:113) ~[feign-core-10.1.0.jar!/:na]
at feign.SynchronousMethodHandler.invoke(SynchronousMethodHandler.java:78) ~[feign-core-10.1.0.jar!/:na]
at feign.ReflectiveFeign$FeignInvocationHandler.invoke(ReflectiveFeign.java:103) ~[feign-core-10.1.0.jar!/:na]
at com.sun.proxy.$Proxy141.creditReportConvert(Unknown Source) ~[na:na]
Caused by: java.net.SocketTimeoutException: Read timed out
at java.net.SocketInputStream.socketRead0(Native Method) ~[na:1.8.0_121]
at java.net.SocketInputStream.socketRead(SocketInputStream.java:116) ~[na:1.8.0_121]
at java.net.SocketInputStream.read(SocketInputStream.java:171) ~[na:1.8.0_121]
at java.net.SocketInputStream.read(SocketInputStream.java:141) ~[na:1.8.0_121]
at java.io.BufferedInputStream.fill(BufferedInputStream.java:246) ~[na:1.8.0_121]
at java.io.BufferedInputStream.read1(BufferedInputStream.java:286) ~[na:1.8.0_121]
at java.io.BufferedInputStream.read(BufferedInputStream.java:345) ~[na:1.8.0_121]
at sun.net.www.http.HttpClient.parseHTTPHeader(HttpClient.java:704) ~[na:1.8.0_121]
at sun.net.www.http.HttpClient.parseHTTP(HttpClient.java:647) ~[na:1.8.0_121]
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1569) ~[na:1.8.0_121]
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1474) ~[na:1.8.0_121]
at java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:480) ~[na:1.8.0_121]
at feign.Client$Default.convertResponse(Client.java:143) ~[feign-core-10.1.0.jar!/:na]
at feign.Client$Default.execute(Client.java:68) ~[feign-core-10.1.0.jar!/:na]
at org.springframework.cloud.openfeign.ribbon.FeignLoadBalancer.execute(FeignLoadBalancer.java:93) ~[spring-cloud-openfeign-core-2.1.1.RELEASE.jar!/:2.1.1.RELEASE]
at org.springframework.cloud.openfeign.ribbon.FeignLoadBalancer.execute(FeignLoadBalancer.java:56) ~[spring-cloud-openfeign-core-2.1.1.RELEASE.jar!/:2.1.1.RELEASE]
at com.netflix.client.AbstractLoadBalancerAwareClient$1.call(AbstractLoadBalancerAwareClient.java:104) ~[ribbon-loadbalancer-2.3.0.jar!/:2.3.0]
at com.netflix.loadbalancer.reactive.LoadBalancerCommand$3$1.call(LoadBalancerCommand.java:303) ~[ribbon-loadbalancer-2.3.0.jar!/:2.3.0]
通过系统慢请求捕捉拦截，发现当前请求仅耗时1031毫秒，就触发Read timed out超时错误，本项目与下游项目均注册在Eureka上面，对这个1秒就超时感到很迷惑，于是开始查阅底层源码之旅。
通过跟踪代码可以在feign.Request内部类Options构造函数默认配置连接超时10秒，读超时60秒。然而本次调用请求仅耗时1秒左右就被掐断连接提示超时错误，初步判断默认这个超时配置并未生效导致。
写到这，咱们先回顾下Feign链路完整调用流程步骤。
可以看出Feign调用分为Hystrix、Ribbon两层，一般高版本的Hystrix默认是关闭的（本项目Hystrix默认是关闭的，那么现在需要去分析Ribbon层调用配置信息）
可以看到RibbonClientConfiguration默认配置的读超时和连接超时时间1000毫秒=1秒，在没有配置超时情况下当前这个超时是符合本次调用超时错误触发。
我们可以在FeignLoadBalancer的execute方法中看到当IClientConfig为空的时候进行覆盖超时时间，默认是取Ribbon的超时时间，并不是Feign Options默认的超时时间。
public FeignLoadBalancer(ILoadBalancer lb, IClientConfig clientConfig,
ServerIntrospector serverIntrospector) {
super(lb, clientConfig);
this.setRetryHandler(RetryHandler.DEFAULT);
this.clientConfig = clientConfig;
this.ribbon = RibbonProperties.from(clientConfig);
RibbonProperties ribbon = this.ribbon;
this.connectTimeout = ribbon.getConnectTimeout();
this.readTimeout = ribbon.getReadTimeout();
this.serverIntrospector = serverIntrospector;
}如果application.properties文件中有配置超时时间，则使用配置的超时时间。否则是取Ribbon默认的超时时间，也就是网上所说的Feign调用服务的默认时长是1秒钟，也就是如果超过1秒没连接上或者超过1秒没响应，那么会相应的报错。
实际业务中服务如果响应时间超过1秒，咱们可以按照实际响应情况给予配置相对应的超时时间，下面分别贴出properties和yml版本的配置
#properties版本
feign.client.config.default.connectTimeout=60000
feign.client.config.default.readTimeout=60000
#yml版本
feign:
client:
config:
default:
connectTimeout: 60000
readTimeout: 60000到此这篇关于记一次线上SpringCloud Feign请求服务超时异常排查的文章就介绍到这了,更多相关SpringCloud Feign请求服务超时内容请搜索编程网以前的文章或继续浏览下面的相关文章希望大家以后多多支持编程网！
