更正java代码以提高可伸缩性

Question

"http-nio-8080-exec-1415" #88733 daemon prio=5 os_prio=0 tid=0x00007f98c03d1800 nid=0x2240f in Object.wait() [0x00007f9744dcb000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
    at java.lang.Object.wait(Native Method)
    at org.apache.tomcat.util.net.NioEndpoint$NioSocketWrapper.fillReadBuffer(NioEndpoint.java:1244)
    - locked <0x00000007762846e0> (a java.util.concurrent.Semaphore)
    at org.apache.tomcat.util.net.NioEndpoint$NioSocketWrapper.read(NioEndpoint.java:1158)
    at org.apache.coyote.http11.Http11InputBuffer.fill(Http11InputBuffer.java:736)
    at org.apache.coyote.http11.Http11InputBuffer.access$300(Http11InputBuffer.java:42)
    at org.apache.coyote.http11.Http11InputBuffer$SocketInputBuffer.doRead(Http11InputBuffer.java:1099)
    at org.apache.coyote.http11.filters.IdentityInputFilter.doRead(IdentityInputFilter.java:102)
    at org.apache.coyote.http11.Http11InputBuffer.doRead(Http11InputBuffer.java:247)
    at org.apache.coyote.Request.doRead(Request.java:551)
    at org.apache.catalina.connector.InputBuffer.realReadBytes(InputBuffer.java:336)
    at org.apache.catalina.connector.InputBuffer.checkByteBufferEof(InputBuffer.java:632)
    at org.apache.catalina.connector.InputBuffer.read(InputBuffer.java:362)
    at org.apache.catalina.connector.CoyoteInputStream.read(CoyoteInputStream.java:132)
    at com.fasterxml.jackson.core.json.UTF8StreamJsonParser._loadMore(UTF8StreamJsonParser.java:205)
    at com.fasterxml.jackson.core.json.UTF8StreamJsonParser._loadMoreGuaranteed(UTF8StreamJsonParser.java:2342)
    at com.fasterxml.jackson.core.json.UTF8StreamJsonParser._finishString2(UTF8StreamJsonParser.java:2427)
    at com.fasterxml.jackson.core.json.UTF8StreamJsonParser._finishAndReturnString(UTF8StreamJsonParser.java:2407)
    at com.fasterxml.jackson.core.json.UTF8StreamJsonParser.getText(UTF8StreamJsonParser.java:269)
    at com.fasterxml.jackson.databind.deser.std.BaseNodeDeserializer.deserializeObject(JsonNodeDeserializer.java:264)
    at com.fasterxml.jackson.databind.deser.std.BaseNodeDeserializer.deserializeArray(JsonNodeDeserializer.java:434)
    at com.fasterxml.jackson.databind.deser.std.BaseNodeDeserializer.deserializeObject(JsonNodeDeserializer.java:258)
    at com.fasterxml.jackson.databind.deser.std.BaseNodeDeserializer.deserializeArray(JsonNodeDeserializer.java:434)
    at com.fasterxml.jackson.databind.deser.std.JsonNodeDeserializer.deserialize(JsonNodeDeserializer.java:70)
    at com.fasterxml.jackson.databind.deser.std.JsonNodeDeserializer.deserialize(JsonNodeDeserializer.java:15)
    at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:129)
    at com.fasterxml.jackson.databind.deser.BeanDeserializer.vanillaDeserialize(BeanDeserializer.java:288)
    at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:151)
    at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:286)
    at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:245)
    at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:27)
    at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:129)
    at com.fasterxml.jackson.databind.deser.BeanDeserializer.vanillaDeserialize(BeanDeserializer.java:288)
    at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:151)
    at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4014)
    at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3071)
    at com.myapp.controller.MyController.populate(PublishController.java:69)
    at sun.reflect.GeneratedMethodAccessor140.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:105)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:893)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:798)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:660)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at com.myapp.security.SecurityFilter.doFilterInternal(SecurityOAuthFilter.java:174)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.springframework.boot.actuate.web.trace.servlet.HttpTraceFilter.doFilterInternal(HttpTraceFilter.java:88)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.springframework.web.filter.CorsFilter.doFilterInternal(CorsFilter.java:97)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:114)
    at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:104)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:367)
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1639)
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    - locked <0x0000000776284588> (a org.apache.tomcat.util.net.NioEndpoint$NioSocketWrapper)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:748)

将近200个nio线程处于相同的状态。可以做什么来使它的代码更可伸缩性，这样我们将获得更高的吞吐量。

Answer 1

好的，如果我正确地读取了stacktrace，那么这是一个正在处理Servlet请求的工作线程，并且它在对MyController类中的Populate的调用中被阻塞。populate方法似乎正在从读取HTTP连接的流中反序列化JSON。我不确定这是来自原始请求的POST数据，还是来自发送到后端服务器的请求的响应数据。不管怎样...

如果您有很多线程处于这种状态,那么最可能出现的问题是：

>

获取JSON的网络路径上存在网络拥塞。

您的服务器跟不上。

没有什么灵丹妙药可以使这样的服务更具可伸缩性。可能的解决办法可能包括：

• 增加前端（或后端）网络带宽。
• 复制前端服务器并在其前面放置负载均衡器。
• 提高后端服务的性能。
• 研究更改应用程序设计，以便无需在前端与用户和/或后端与前端之间传递如此多的数据。
• 调查缓存是否可能减少前端/后端通信量。
• 如果瓶颈是CPU而不是I/O，请考虑使用具有较低序列化/反序列化开销的表示形式来替换JSON。