Tomcat服务org.springframework.web.util.NestedServletException: Handler processing failed; nested exception is java.lang.OutOfMemoryError: Java heap space

一个运行了很久的项目，最近忽然报错：OOM( java.lang.OutOfMemoryError: Java heap space)，异常如下

org.springframework.web.util.NestedServletException: Handler processing failed; nested exception is java.lang.OutOfMemoryError: Java heap space
    at org.springframework.web.servlet.DispatcherServlet.triggerAfterCompletionWithError(DispatcherServlet.java:1305)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:979)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:895)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:967)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:869)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:843)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:184)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:217)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:184)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:121)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:217)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:184)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:105)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:361)
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:1080)
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:75)
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:757)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1515)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.OutOfMemoryError: Java heap space

程序运行时内存分为堆(Stack)内存和栈(Heap)内存

凭借着初略的c语言知识来分析这个问题,理解如下：

1、栈内存的特性是快用快销，不需要手工去释放、管理；（网络问题、文件系统、消息循环、不合理的递归等操作也会导致栈开销过大，甚至溢出StackOverFlowError）

2、堆内存的特性是谁用谁销（c语言中说法：谁申请谁释放）

那么根据异常来甄别一下，一定是程序不合理的使用使用内存导致整个问题，而OOM异常一般是硬件级别的异常。

查了一下服务器，32G的内存，不应该出现这种问题的。

由于tomcat是通过服务方式运行的，more分配的内存如下

Initial memory pool(初始化堆内存) 128M 对应-Xms参数

Maximun memory pool(最大堆内存) 256M 对应-Xmx参数

由于端午节期间放假，增量数据累计到33万，没有人去处理，程序在自动运行的时候尝试申请堆内存，触顶了（256M），所以报这个错误。

解决方法：增大初始化堆内存，最大堆内存

Initial memory pool改为1024M

Maximun memory pool 10240M

另外在Java Option里面添加以下参数

-XX:PermSize=256M  //初始化类加载内存池大小 
-XX:MaxPermSize=256M //最大类加载内存池大小 
-XX:MaxNewSize=256M 

优化后如下

参考：Tomcat启动内存设置【转载】