我们将tomcat 7与Spring 4.2.5和Spring-MVC一起使用。我们有一些客户也可以调用的REST接口。最近，我们包括了jackson XML（来自fastxml），因此可以使用jackson而不是JAXB处理XML接口。从那时起，在tomcat重新启动后，CPU负载随着时间的流逝而越来越大，导致数小时后100％的CPU负载。
我们能够查明原因是我们的一位客户经常致电的特定REST XML POST接口。我们还能够观察到此类请求失败，并出现HTTP 499 ClientClosedRequest错误。这些499的数量与我们通过kill -3检索到的锁定线程的数量一致。
这些锁定线程的堆栈跟踪如下：
"catalina-exec-1" #50 daemon prio=5 os_prio=0 tid=0x00007f11c0001800 nid=0x1d89 runnable [0x00007f11f46e6000]
java.lang.Thread.State: RUNNABLE
at com.sun.xml.stream.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:353)
at com.sun.xml.stream.XMLReaderImpl.next(XMLReaderImpl.java:565)
at com.fasterxml.jackson.dataformat.xml.XmlFactory._initializeXmlReader(XmlFactory.java:653)
at com.fasterxml.jackson.dataformat.xml.XmlFactory._createParser(XmlFactory.java:536)
at com.fasterxml.jackson.dataformat.xml.XmlFactory._createParser(XmlFactory.java:29)
at com.fasterxml.jackson.core.JsonFactory.createParser(JsonFactory.java:820)
at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3084)
at org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.readJavaType(AbstractJackson2HttpMessageConverter.java:222)
at org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.read(AbstractJackson2HttpMessageConverter.java:209)
at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodArgumentResolver.readWithMessageConverters(AbstractMessageConverterMethodArgumentResolver.java:197)
at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.readWithMessageConverters(RequestResponseBodyMethodProcessor.java:147)
at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.resolveArgument(RequestResponseBodyMethodProcessor.java:125)
at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:99)
at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:161)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:128)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:817)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:731)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:968)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:870)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:646)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:844)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:316)
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:126)
at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:90)
我们无法根据自己的要求复制此内容。我们甚至试图通过过早中止我们的请求来引发499错误，但无济于事。 即使我们要重现此问题-既然Spring和Jackson都在做所有工作，我们怎么能实际解决这个问题。
不幸的是，由于我们的某些新功能依赖于jackson，因此无法返回JAXB。