RE: Tomcat service crashes unexpectedly, no trace in logs
Hi Greg,
Thanks, great idea, I'm certainly going to try it out asap. However, at this
point I don't think we're chasing the same problem (correct me if I'm wrong):
In your case there is not really a crash, as opposed to my situation where I
can see a message in the Windows Event Log + I also found a DrWatson dump
(user.dump)
I've browsed through the DrWatson dump-file, but there doesn't seem to be much
useful information in there. Of course, I can really say this being an expert
in analysing binary data in dump files and all :-)
Seriously though, could there be perhaps some indicators I can use to be sure
this is either a Jvm XOR a Tomcat problem ?
David
-Original Message-
From: Greg Lappen [mailto:[EMAIL PROTECTED]
Sent: vrijdag 14 januari 2005 22:25
To: Tomcat Users List
Subject: Re: Tomcat service crashes unexpectedly, no trace in logs
David,
I have been chasing a similar problem for weeks now with tomcat 5.0.28
on Linux. It occurs sporadically, sometimes a couple times a day,
sometimes after weeks. I see no errors in the log file and no core
dumps. At first I thought it was the JVM crashing but I've tracked it
down to the JVM shutting down normally somehow, as if somewhere
System.exit was being called. I put a security policy in place and
enabled the security manager to prevent the System.exit call so I
should find the culprit in my log files the next time its called.
To test if this is what's happening, add a shutdownHook when your app
starts like this:
public class ExitListener implements ServletContextListener {
public void contextInitialized(ServletContextEvent event) {
Runtime.getRuntime().addShutdownHook(new ExitListenerThread());
System.out.println(ExitListener installed shutdown hook);
}
public void contextDestroyed(ServletContextEvent event) {
System.out.println(ExitListener.contextDestroyed());
}
}
public class ExitListenerThread extends Thread {
public void run() {
System.out.println(ExitListenerThread running!!!);
System.out.println(current time is: + new java.util.Date());
}
}
Hope this helps.
Greg
On Jan 14, 2005, at 2:04 PM, David Vandaele wrote:
Hi,
We're experiencing Tomcat crashes during stresstesting of a
webapplication.
Situation: Tomcat runs as a Windows service. During stresstests the
Tomcat-services suddenly ends unexpectedly. The Windows eventlog
logs states something like: ...service ended unexpectedly... The
problem is not easily or consistently reproducable...
When I look at all the logs of Tomcat and of our webapplication, no
mention of an exception or error or crash whatsoever !(?) (They all
just stop abruptly)
First I thought it was an OutOfMemoryError problem. I forced an
OutOfMemoryError myself by limiting the memory of the JVM of Tomcat
severely. But then I could see loggings of an OutOfMemoryError in the
Tomcat stderr-log, which is not what I expected because I didn't
expect any loggings of a crash at all...
The problem only *seems* to occur when the servermachine is completely
left alone (not logged in or locked) Additionally, it usually occurs
after between 30-70 minutes or so. When I keep monitoring the machine
while the same tests are running the crash doesn't seem to occur ?!
Could it be a power-saving issue, like e.g. with the network-adaptor ?
Then I would not expect a crash, but a stacktrace ?
I tried adding a try-catch(Throwable) around a method where everything
starts (the process method of my Struts ActionServlet). I've been
trying to reproduce the problem since, but as I mentioned, it's not
consistently reproducable...
I've searched the net trying to find related problems, or a JVM
problem of some kind with this version, haven't been successful
though... If it is a problem with bad memory, I would expect to see
different behaviour, like more random crashes, not only of the Tomcat
service...
Environment: Tomcat 4.1.29, JDK 1.4.2_03, Windows 2000ProSP4,
bi-processor Xeon machine.
Any help/advice/ideas is really welcome and appreciated !
Kind regards,
David
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RE: Still having OutOfMemory Problems (Tomcat 4.1.31)
Try printing out this: Runtime.getRuntime().freeMemory(): Runtime.getRuntime().maxMemory(); Check out the API if you want to know the exact meaning of these methods, but they are pretty obvious I think. Now print these somewhere you know you'll get before the OutOfMemError occurs, or some place like the service() method or something. David -Original Message- From: David Johnson [mailto:[EMAIL PROTECTED] Sent: maandag 17 januari 2005 18:52 To: Tomcat Users List Subject: Still having OutOfMemory Problems (Tomcat 4.1.31) HI all. Well I'm still getting my out of memory problem fairly consistently (again) using Tomcat 4.1.31 with my Struts application. When I look st the memory usage, it says tomcat is using about 110k of memory for the VM, but that's just looking at the task manager. Tomcat is installed as a service using a bat file (follows). Note the -Xms128M and -Xmx512M options are set...if doesnt seem to matter what I set these options toeven if I set them to 32m/64m! How can I tell if tomcat is REALLY using those settings? It doesnt seem to be Thanks - install.bat: @SET JAVA_HOME=C:\j2sdk_1_4_0_2 @SET TOMCAT_HOME=C:\Tomcat4.1 @SET TOMCAT_JVM=%JAVA_HOME%\jre\bin\client\jvm.dll @SET TOMCAT_CLASSPATH=%TOMCAT_HOME%\bin\bootstrap.jar;%TOMCAT_HOME%\common\lib\servlet.jar @SET TOMCAT_ENDORSED=%TOMCAT_HOME%\common\endorsed @SET TOMCAT_LOG=%TOMCAT_HOME%\logs\stdout.log @SET TOMCAT_ERR_LOG=%TOMCAT_HOME%\logs\stderr.log %TOMCAT_HOME%\bin\tomcat.exe -install Apache Tomcat 4.1.31 %TOMCAT_JVM% -Djava.class.path=%TOMCAT_CLASSPATH% -DXms128M -DXmx512M -DXX:+PrintTenuringDistribution -DXX:+PrintGCDetails -Xverbosegc -Djava.endorsed.dirs=%TOMCAT_ENDORSED% -Dcatalina.home=%TOMCAT_HOME% -start org.apache.catalina.startup.BootstrapService -params start -stop org.apache.catalina.startup.BootstrapService -params stop -out %TOMCAT_LOG% -err %TOMCAT_ERR_LOG% - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Tomcat service crashes unexpectedly, no trace in logs
Hi, We're experiencing Tomcat crashes during stresstesting of a webapplication. Situation: Tomcat runs as a Windows service. During stresstests the Tomcat-services suddenly ends unexpectedly. The Windows eventlog logs states something like: ...service ended unexpectedly... The problem is not easily or consistently reproducable... When I look at all the logs of Tomcat and of our webapplication, no mention of an exception or error or crash whatsoever !(?) (They all just stop abruptly) First I thought it was an OutOfMemoryError problem. I forced an OutOfMemoryError myself by limiting the memory of the JVM of Tomcat severely. But then I could see loggings of an OutOfMemoryError in the Tomcat stderr-log, which is not what I expected because I didn't expect any loggings of a crash at all... The problem only *seems* to occur when the servermachine is completely left alone (not logged in or locked) Additionally, it usually occurs after between 30-70 minutes or so. When I keep monitoring the machine while the same tests are running the crash doesn't seem to occur ?! Could it be a power-saving issue, like e.g. with the network-adaptor ? Then I would not expect a crash, but a stacktrace ? I tried adding a try-catch(Throwable) around a method where everything starts (the process method of my Struts ActionServlet). I've been trying to reproduce the problem since, but as I mentioned, it's not consistently reproducable... I've searched the net trying to find related problems, or a JVM problem of some kind with this version, haven't been successful though... If it is a problem with bad memory, I would expect to see different behaviour, like more random crashes, not only of the Tomcat service... Environment: Tomcat 4.1.29, JDK 1.4.2_03, Windows 2000ProSP4, bi-processor Xeon machine. Any help/advice/ideas is really welcome and appreciated ! Kind regards, David - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
