Why is my Tomcat server restarting and what is org.apache.catalina.core.AprLifecycleListener?

Question

I'm trying to figure out why my web app (I didn't write it, but I'm supposed to debug it) is consistently causing the Tomcat web server to restart. All I see in the logs before the server restarts is:

Jul 24, 2009 7:52:15 AM org.apache.catalina.core.AprLifecycleListener lifecycleEvent
INFO: The Apache Portable Runtime which allows optimal performance in production environments was not found on the java.library.path: /usr/local/jdk1.5.0_09/jre/lib/i386/server:/usr/local/jdk1.5.0_09/jre/lib/i386:/usr/local/jdk1.5.0_09/jre/../lib/i386
Jul 24, 2009 7:52:15 AM org.apache.coyote.http11.Http11BaseProtocol init

I can actual do this same processing on other groups of files and it works fine, but doing this one particular group causes the server to restart. Mostly I'm hoping somebody can tell me if that's just a timeout, or if there should be some other log file telling me why it's dying. And if it's a timeout, if there's a way to increase it.

Update: I tried starting the server with bin/catalina.sh run which puts the output to stanadard out instead of catalina.out, and all I get instead of the above is the progress from my app and then "Killed".

As an aside, I don't know what's restarting it, but when I try to restart the server with bin/catalina.sh run, I get a BindException, so something restarted it.

Update 2: It was using Tomcat 5.5 and Java 5. I installed Tomcat 6 and set it up to use Java 6, and the same thing is happening. Also, if I do an "echo $?" after the "Killed", it gives me "137", which probably indicates the hosting company is killing it off for some reason.

Answer 1

Undeploy the webapp and see if Tomcat will come up without it. I suspect a bad Tomcat installation.

Answer 2

I believe that you only see that APR message when the server is first started.

An application deployed in Tomcat should not have the ability to make the entire server stop and start again - that doesn't make a lot of sense. Certain things can be done to make a webapp itself be reloaded (such as changing web.xml, or hitting Reload from Tomcat Manager), but nothing a deployed app does should be able to stop/start the entire server.

Are you sure that there isn't something external stopping and starting the server? A shell script or a cron job somewhere?

Answer 3

I know this is lame, but it is possible that your app is somehow causing System.exit() to be called?

Answer 4

AprLifecycleListener's responsibility is to initialize the Apache Portable Runtime, see http://tomcat.apache.org/tomcat-6.0-doc/apr.html

Could you post the log entries of the shutdown (do you have any, or is the above all you see?)?

BTW, you're saying that tomcat restarts, the standard shell scripts only start tomcat once, they just exit when tomcat quits. Do you have any kind of wrapper software (like http://wrapper.tanukisoftware.org/) that might be restarting your server?

Answer 5

Never mind - it turns out the hosting company was killing my process (with kill -9 no less) because it was taking too much CPU time. Now I have to figure out how to do this incredibly time consuming task without using 90% of their CPU for more than 10 minutes - I tried "nicing" Tomcat and that didn't help, so I may have to add a "sleep(1000)" in the processing loop or something.