tomcat运行一段时间后死掉

在tomcat死掉的时候，catalina.out　记录
Jun 24, 2008 2:11:55 PM org.apache.coyote.http11.Http11Protocol pause
INFO: Pausing Coyote HTTP/1.1 on http-8900
Jun 24, 2008 2:11:55 PM org.apache.jk.common.ChannelSocket acceptConnections
WARNING: Exception executing accept
java.net.SocketException: Invalid argument
at java.net.PlainSocketImpl.socketSetOption(Native Method)
at java.net.PlainSocketImpl.setOption(PlainSocketImpl.java:240)
at java.net.Socket.setSoLinger(Socket.java:814)
at org.apache.jk.common.ChannelSocket.accept(ChannelSocket.java:300)
at org.apache.jk.common.ChannelSocket.acceptConnections(ChannelSocket.java:63
at org.apache.jk.common.SocketAcceptor.runIt(ChannelSocket.java:847)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:683)
at java.lang.Thread.run(Thread.java:534)
Jun 24, 2008 2:11:56 PM org.apache.catalina.core.StandardService stop
INFO: Stopping service Catalina
Jun 24, 2008 2:11:56 PM org.apache.catalina.core.StandardHostDeployer remove
INFO: Removing web application at context path /dmsperfweb
请教
(1)是org.apache.coyote.http11.Http11Protocol pause 导致后续org.apache.catalina.core.StandardService stop
还是org.apache.catalina.core.StandardService stop 之前肯定会执行org.apache.jk.common.ChannelSocket acceptConnections，
即两者的因果关系如何

之后应用日志perfweb.log记录
2008-06-24 14:11:56,292 org.apache.catalina.core.StandardWrapper
INFO : Waiting for 15 instance(s) to be deallocated
2008-06-24 14:11:57,382 org.apache.catalina.core.StandardWrapper
INFO : Waiting for 15 instance(s) to be deallocated
2008-06-24 14:11:58,463 org.apache.catalina.core.StandardWrapper
INFO : Waiting for 15 instance(s) to be deallocated
2008-06-24 14:11:58,577 org.apache.catalina.core.StandardWrapper
INFO : Waiting for 1 instance(s) to be deallocated
2008-06-24 14:11:59,652 org.apache.catalina.core.StandardWrapper
INFO : Waiting for 1 instance(s) to be deallocated
2008-06-24 14:12:00,742 org.apache.catalina.core.StandardWrapper
INFO : Waiting for 1 instance(s) to be deallocated
2008-06-24 14:12:00,857 com.huawei.d2000.perfweb.PerfWebContextListener
INFO : context destroyed

请教
(2)有什么原因会导致tomcat死掉？
谢谢！