我有一个应用程序在 tomcat 上运行,有时会出现以下错误:
SEVERE: Socket accept failed
java.net.SocketException: Too many open files
at java.net.PlainSocketImpl.socketAccept(Native Method)
at java.net.AbstractPlainSocketImpl.accept(AbstractPlainSocketImpl.java:398)
at java.net.ServerSocket.implAccept(ServerSocket.java:522)
at java.net.ServerSocket.accept(ServerSocket.java:490)
at org.apache.tomcat.util.net.DefaultServerSocketFactory.acceptSocket(DefaultServerSocketFactory.java:60)
at org.apache.tomcat.util.net.JIoEndpoint$Acceptor.run(JIoEndpoint.java:216)
at java.lang.Thread.run(Thread.java:722)
....
SEVERE: Error processed default web.xml named conf/web.xml at /local/myApp/apache-tomcat/conf/web.xml
java.io.FileNotFoundException: /local/myApp/apache-tomcat/conf/web.xml (Too many open files)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(FileInputStream.java:138)
at org.apache.catalina.startup.ContextConfig.getWebXmlSource(ContextConfig.java:1838)
at org.apache.catalina.startup.ContextConfig.getGlobalWebXmlSource(ContextConfig.java:1745)
at org.apache.catalina.startup.ContextConfig.getDefaultWebXmlFragment(ContextConfig.java:1418)
at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1253)
at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:878)
at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:369)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5269)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.StandardContext.reload(StandardContext.java:3926)
at org.apache.catalina.loader.WebappLoader.backgroundProcess(WebappLoader.java:426)
at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1345)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1530)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1540)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1540)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1519)
at java.lang.Thread.run(Thread.java:722)
我检查打开文件的限制,它是 1024,但是当我使用 lsof 检查应用程序的打开文件数时,它接近 200,如果没有达到限制,为什么会发生这种情况?
我应该增加限额吗?还有其他原因会出现此错误吗?
让服务再次正常运行的唯一方法是重新启动tomcat,还有其他方法恢复正常吗?
提前致谢。
EDIT:
这是处理 doPost 方法的 servlet,一开始我没有关闭每个流,可能是这样吗?我为此添加了finally声明:
InputStream is = null;
DataInputStream dis = null;
OutputStream os = null;
DataOutputStream dos = null;
String paramName = "";
try {
os = response.getOutputStream();
is = request.getInputStream();
dis = new DataInputStream(is);
dos = new DataOutputStream(os);
.....
}catch (Throwable e) {
LOGGER.error(e.getMessage());
} finally {
if (dis != null) {
dis.close();
}
else if(is != null) {
is.close();
}
if (dos != null) {
dos.close();
}
else if( os != null) {
os.close();
}
}
EDIT2:经过一些测试后,我意识到,如果我先关闭 DataInputStream,然后关闭 InputStream,我会在消息之前获得通信的其他部分的数字(我不知道为什么)。我改变了关闭流的顺序,看起来一切都好。但我仍然有问题。任何想法?
finally {
if(is != null) {
try {
is.close();
} catch (IOException e) {
LOGGER.error(e.getMessage());
}
}
if (dis != null) {
try {
dis.close();
} catch (IOException e) {
LOGGER.error(e.getMessage());
}
}
if(os != null) {
try {
os.close();
} catch (IOException e) {
LOGGER.error(e.getMessage());
}
}
if (dos != null) {
try {
dos.close();
} catch (IOException e) {
LOGGER.error(e.getMessage());
}
}
}