[Wrapper-user] RE: Tomcat NT JVM hung

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Any suggestions in beginning to diagnose our problem would be =
appreciated. Thank you.

>  -----Original Message-----
> From: 	Marsh, Ralph =20
> Sent:	Thursday, March 03, 2005 4:18 PM
> To:	'wra...@li...'
> Subject:	Tomcat NT JVM hung
>=20
> We are running a Struts web app on Tomcat 4.1. We use the wrapper to =
run Tomcat as a service.
>=20
> Over the past 8 months, about once per month, the service has died. =
Within the past month the frequency of these events has gone up to about =
once per week.=20
>=20
> This leaves the web app dead in the water, the user receiving HTTP 500 =
errors and us logging into the NT box and manually restarting the =
service. We have the wrapper.conf file set to output STATUS level =
messages to the log. In the log we see this:
>=20
> ERROR  | wrapper  | 2005/03/03 17:58:43 | JVM appears hung: Timed out =
waiting for signal from JVM.
> ERROR  | wrapper  | 2005/03/03 17:58:43 | Java Virtual Machine did not =
exit on request, terminated
> STATUS | wrapper  | 2005/03/03 17:58:49 | Launching a JVM...
> STATUS | wrapper  | 2005/03/03 17:59:03 | <-- Wrapper Stopped
>=20
> I have four questions:
> 1) what can cause a JVM backing Tomcat to hang?
> 2) how should I configure the wrapper to get the most useful logging =
information during these events? Running in DEBUG for a week/weeks will =
produce copious logs. If necessary, I'll do it, but is it necessary?
> 3) isn't the wrapper supposed to recognize these hangs, gracefully =
kill the process then restart a new process? If so, what should I look =
at to determine why this is not happening in our case
> 4) in the log output above what is going on between the third and =
forth entry? It appears a new JVM is launching then the wrapper stops =
everything. Why?
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> Our complete wrapper.conf file is included below. Thank you.
>=20
> Ralph Marsh
>=20
> #********************************************************************
> # Wrapper Properties
> #********************************************************************
> # Java Application
> wrapper.java.command=3D%java_home%\bin\java
>=20
> # Java Main class.  This class must implement the WrapperListener =
interface
> #  or guarantee that the WrapperManager class is initialized.  Helper
> #  classes are provided to do this for you.  See the Integration =
section
> #  of the documentation for details.
> =
wrapper.java.mainclass=3Dorg.tanukisoftware.wrapper.WrapperStartStopApp
>=20
> # Java Classpath (include wrapper.jar)  Add class path elements as
> #  needed starting from 1
> wrapper.java.classpath.1=3D../common/lib/wrapper.jar
> wrapper.java.classpath.2=3D%java_home%/lib/tools.jar
> wrapper.java.classpath.3=3D../bin/bootstrap.jar
>=20
> # Java Library Path (location of Wrapper.DLL or libwrapper.so)
> wrapper.java.library.path.1=3D../common/lib
>=20
> # Java Additional Parameters
> wrapper.java.additional.1=3D-server
> wrapper.java.additional.2=3D-XX:+UseParNewGC
> wrapper.java.additional.3=3D-XX:MaxNewSize=3D24m
> wrapper.java.additional.4=3D-XX:NewSize=3D24m
> wrapper.java.additional.5=3D-XX:SurvivorRatio=3D128
> wrapper.java.additional.6=3D-XX:+UseConcMarkSweepGC
> wrapper.java.additional.7=3D-XX:MaxTenuringThreshold=3D0
> wrapper.java.additional.8=3D-XX:CMSInitiatingOccupancyFraction=3D60
> =
wrapper.java.additional.9=3D-Djava.endorsed.dirs=3D../bin;../common/endor=
sed
> wrapper.java.additional.10=3D-Dcatalina.base=3D..
> wrapper.java.additional.11=3D-Dcatalina.home=3D..
> wrapper.java.additional.12=3D-Djava.io.tmpdir=3D../temp
>                        =20
> #wrapper.java.additional.13=3D-verbosegc
> #wrapper.java.additional.14=3D-XX:+PrintGCTimeStamps
> #wrapper.java.additional.15=3D-XX:+PrintGCDetails
> #wrapper.java.additional.13=3D-XX:+PrintTenuringDistribution
>=20
>=20
> #wrapper.java.additional.7=3D-verbosegc
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> # Initial Java Heap Size (in MB)
> wrapper.java.initmemory=3D1200
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> # Maximum Java Heap Size (in MB)
> wrapper.java.maxmemory=3D1200
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> # Application parameters.  Add parameters as needed starting from 1
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> # The first application parameter is the name of the class whose main> =

> # method is to be called when the application is launched.  The class
> # name is followed by the number of parameters to be passed to its =
main
> # method.  Then comes the actual parameters.
> wrapper.app.parameter.1=3Dorg.apache.catalina.startup.Bootstrap
> wrapper.app.parameter.2=3D1
> wrapper.app.parameter.3=3Dstart
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> # The start parameters are followed by the name of the class whose =
main
> # method is to be called to stop the application.  The stop class name
> # is followed by a flag which controls whether or not the Wrapper =
should
> # wait for all non daemon threads to complete before exiting the JVM.
> # The flag is followed by the number of parameters to be passed to the
> # stop class's main method.  Finally comes the actual parameters.
> wrapper.app.parameter.4=3Dorg.apache.catalina.startup.Bootstrap
> wrapper.app.parameter.5=3Dtrue
> wrapper.app.parameter.6=3D1
> wrapper.app.parameter.7=3Dstop
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> #********************************************************************
> # Wrapper Logging Properties
> #********************************************************************
> # Format of output for the console.  (See docs for formats)
> wrapper.console.format=3DPM
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> # Log Level for console output.  (See docs for log levels)
> wrapper.console.loglevel=3DINFO
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> # Log file to use for wrapper output logging.
> wrapper.logfile=3D../logs/wrapper.log
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> # Format of output for the log file.  (See docs for formats)
> wrapper.logfile.format=3DLPTM
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> # Log Level for log file output.  (See docs for log levels)
> wrapper.logfile.loglevel=3DSTATUS
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> # Maximum size that the log file will be allowed to grow to before
> #  the log is rolled. Size is specified in bytes.  The default value
> #  of 0, disables log rolling.  May abbreviate with the 'k' (kb) or
> #  'm' (mb) suffix.  For example: 10m =3D 10 megabytes.
> wrapper.logfile.maxsize=3D500k
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> # Maximum number of rolled log files which will be allowed before old
> #  files are deleted.  The default value of 0 implies no limit.
> wrapper.logfile.maxfiles=3D0
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> # Log Level for sys/event log output.  (See docs for log levels)
> wrapper.syslog.loglevel=3DNONE
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> #********************************************************************
> # Wrapper NT Service Properties
> #********************************************************************
> # WARNING - Do not modify any of these properties when an application
> #  using this configuration file has been installed as a service.
> #  Please uninstall the service before modifying this section.  The
> #  service can then be reinstalled.
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> # Name of the service
> wrapper.ntservice.name=3Dtomcat-rights2a
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> # Display name of the service
> wrapper.ntservice.displayname=3Dtomcat-rights2a
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> # Description of the service
> wrapper.ntservice.description=3Dtomcat-rights2a
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> # Service dependencies.  Add dependencies as needed starting from 1
> wrapper.ntservice.dependency.1=3D
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> # Mode in which the service is installed.  AUTO_START or DEMAND_START
> wrapper.ntservice.starttype=3DAUTO_START
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> # Allow the service to interact with the desktop.
> wrapper.ntservice.interactive=3Dfalse
>=20