org.apache.catalina.connector.ClientAbortException: java.io.IOException: Connection reset by peer at org.apache.catalina.connector.OutputBuffer.realWriteBytes(OutputBuffer.java:407) at org.apache.tomcat.util.buf.ByteChunk.flushBuffer(ByteChunk.java:480) at org.apache.tomcat.util.buf.ByteChunk.append(ByteChunk.java:366) at org.apache.catalina.connector.OutputBuffer.writeBytes(OutputBuffer.java:432) at org.apache.catalina.connector.OutputBuffer.write(OutputBuffer.java:420) at org.apache.catalina.connector.CoyoteOutputStream.write(CoyoteOutputStream.java:91) at com.dtxxsoft.spm.sys.controller.SpmUploadFileController.download(SpmUploadFileController.java:299) at sun.reflect.GeneratedMethodAccessor1477.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at com.chinasofti.ro.bizframework.core.utils.ActionInvokerUtil.invoke(ActionInvokerUtil.java:207) at com.chinasofti.ro.bizframework.core.mvc.ActionInvoker.invoke(ActionInvoker.java:181) at com.chinasofti.ro.bizframework.core.mvc.ActionFilter.doFilter(ActionFilter.java:179) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at com.chinasofti.ro.bizframework.core.web.filter.DisableUrlSessionFilter.doFilter(DisableUrlSessionFilter.java:59) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at com.chinasofti.ro.bizframework.core.web.filter.LocaleFilter.doFilterInternal(LocaleFilter.java:65) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:96) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at com.dtxxsoft.spm.sys.filter.SSOFilter.doFilter(SSOFilter.java:162) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at com.chinasofti.ro.bizframework.core.web.filter.InitialFilter.doFilter(InitialFilter.java:70) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169) at com.googlecode.psiprobe.Tomcat70AgentValve.invoke(Tomcat70AgentValve.java:38) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:436) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1749) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1708) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$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) Caused by: java.io.IOException: Connection reset by peer at sun.nio.ch.FileDispatcherImpl.write0(Native Method) at sun.nio.ch.SocketDispatcher.write(SocketDispatcher.java:47) at sun.nio.ch.IOUtil.writeFromNativeBuffer(IOUtil.java:93) at sun.nio.ch.IOUtil.write(IOUtil.java:65) at sun.nio.ch.SocketChannelImpl.write(SocketChannelImpl.java:471) at org.apache.tomcat.util.net.NioChannel.write(NioChannel.java:125) at org.apache.tomcat.util.net.NioBlockingSelector.write(NioBlockingSelector.java:101) at org.apache.tomcat.util.net.NioSelectorPool.write(NioSelectorPool.java:174) at org.apache.coyote.http11.InternalNioOutputBuffer.writeToSocket(InternalNioOutputBuffer.java:163) at org.apache.coyote.http11.InternalNioOutputBuffer.flushBuffer(InternalNioOutputBuffer.java:242) at org.apache.coyote.http11.InternalNioOutputBuffer.addToBB(InternalNioOutputBuffer.java:213) at org.apache.coyote.http11.InternalNioOutputBuffer.access$000(InternalNioOutputBuffer.java:41) at org.apache.coyote.http11.InternalNioOutputBuffer$SocketOutputBuffer.doWrite(InternalNioOutputBuffer.java:268) at org.apache.coyote.http11.filters.ChunkedOutputFilter.doWrite(ChunkedOutputFilter.java:119) at org.apache.coyote.http11.AbstractOutputBuffer.doWrite(AbstractOutputBuffer.java:192) at org.apache.coyote.Response.doWrite(Response.java:499) at org.apache.catalina.connector.OutputBuffer.realWriteBytes(OutputBuffer.java:402) ... 48 more
首先贴出了服务器报错信息，主要是服务器同时处理的请求超过了限制，导致宕机。总结出两个方向去解决问题。
- 修改连接超时时间connectionTimeout
- 修改最大线程数及最大排队数maxThreads、acceptCount
修改的文件均是Tomcat-》conf-》server.xml
其中最后两个参数意义如下：
maxThreads：tomcat起动的最大线程数，即同时处理的任务个数，默认值为200
acceptCount：当tomcat起动的线程数达到最大时，接受排队的请求个数，默认值为100
这两个值如何起作用，请看下面三种情况
情况1：接受一个请求，此时tomcat起动的线程数没有到达maxThreads，tomcat会起动一个线程来处理此请求。
情况2：接受一个请求，此时tomcat起动的线程数已经到达maxThreads，tomcat会把此请求放入等待队列，等待空闲线程。
情况3：接受一个请求，此时tomcat起动的线程数已经到达maxThreads，等待队列中的请求个数也达到了acceptCount，此时tomcat会直接拒绝此次请求，返回connection refused
maxThreads如何配置
一般的服务器操作都包括量方面：1计算（主要消耗cpu），2等待（io、数据库等）
第一种极端情况，如果我们的操作是纯粹的计算，那么系统响应时间的主要限制就是cpu的运算能力，此时maxThreads应该尽量设的小，降低同一时间内争抢cpu的线程个数，可以提高计算效率，提高系统的整体处理能力。
第二种极端情况，如果我们的操作纯粹是IO或者数据库，那么响应时间的主要限制就变为等待外部资源，此时maxThreads应该尽量设的大，这样才能提高同时处理请求的个数，从而提高系统整体的处理能力。此情况下因为tomcat同时处理的请求量会比较大，所以需要关注一下tomcat的虚拟机内存设置和linux的open file限制。