docs/application-development-guide/src/main/jbake/content/debugging-apps.adoc - glassfish - Git at Google


            
            type=page

            
            status=published

            
            title=Debugging Applications

            
            next=part-apps-and-app-comps.html

            
            prev=class-loaders.html

            
            ~~~~~~

            
            Debugging Applications

            
            ======================


            [[GSDVG00004]][[beafc]]


            [[debugging-applications]]

            
            3 Debugging Applications

            
            ------------------------


            This chapter gives guidelines for debugging applications in the Oracle

            
            GlassFish Server.


            The following topics are addressed here:


            * link:#beafd[Enabling Debugging]

            
            * link:#beafe[JPDA Options]

            
            * link:#beaff[Generating a Stack Trace for Debugging]

            
            * link:#gekvq[Application Client Debugging]

            
            * link:#beafk[Open Message Queue Debugging]

            
            * link:#beafl[Enabling Verbose Mode]

            
            * link:#gkpdk[Class Loader Debugging]

            
            * link:#beafm[GlassFish Server Logging]

            
            * link:#beafn[Profiling Tools]


            [[beafd]][[GSDVG00101]][[enabling-debugging]]


            Enabling Debugging

            
            ~~~~~~~~~~~~~~~~~~


            When you enable debugging, you enable both local and remote debugging.

            
            To start the server in debug mode, use the `--debug` option as follows:


            [source,oac_no_warn]

            
            ----

            
            asadmin start-domain --debug [domain-name]

            
            ----


            You can then attach to the server from the Java Debugger (`jdb`) at its

            
            default Java Platform Debugger Architecture (JPDA) port, which is 9009.

            
            For example, for UNIX systems:


            [source,oac_no_warn]

            
            ----

            
            jdb -attach 9009

            
            ----


            For Windows:


            [source,oac_no_warn]

            
            ----

            
            jdb -connect com.sun.jdi.SocketAttach:port=9009

            
            ----


            For more information about the `jdb` debugger, see the following links:


            * Java Platform Debugger Architecture - The Java Debugger:

            
            `http://java.sun.com/javase/technologies/core/toolsapis/jpda/`

            
            * Java Platform Debugger Architecture - Connecting with JDB:

            
            `http://java.sun.com/javase/technologies/core/toolsapis/jpda/`


            GlassFish Server debugging is based on the JPDA. For more information,

            
            see link:#beafe[JPDA Options].


            You can attach to the GlassFish Server using any JPDA compliant

            
            debugger, including that of http://www.netbeans.org[NetBeans]

            
            (`http://www.netbeans.org`), Java Studio Enterprise, JBuilder, Eclipse,

            
            and so on.


            You can enable debugging even when the GlassFish Server is started

            
            without the `--debug` option. This is useful if you start the GlassFish

            
            Server from the Windows Start Menu, or if you want to make sure that

            
            debugging is always turned on.


            [[fvyit]][[GSDVG00049]][[to-set-the-server-to-automatically-start-up-in-debug-mode]]


            To Set the Server to Automatically Start Up in Debug Mode

            
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^


            1.  Use the Administration Console. Select the JVM Settings component

            
            under the relevant configuration.

            
            2.  Check the Debug Enabled box.

            
            3.  To specify a different port (from 9009, the default) to use when

            
            attaching the JVM software to a debugger, specify `address=` port-number

            
            in the Debug Options field.

            
            4.  To add JPDA options, add any desired JPDA debugging options in Debug

            
            Options. See link:#beafe[JPDA Options].


            [[GSDVG532]]


            See Also


            For details, click the Help button in the Administration Console from

            
            the JVM Settings page.


            [[beafe]][[GSDVG00102]][[jpda-options]]


            JPDA Options

            
            ~~~~~~~~~~~~


            The default JPDA options in GlassFish Server are as follows:


            [source,oac_no_warn]

            
            ----

            
            -Xdebug -agentlib:transport=dt_socket,server=y,suspend=n,address=9009

            
            ----


            For Windows, you can change `dt_socket` to `dt_shmem`.


            If you substitute `suspend=y`, the JVM software starts in suspended mode

            
            and stays suspended until a debugger attaches to it. This is helpful if

            
            you want to start debugging as soon as the JVM software starts.


            To specify a different port (from 9009, the default) to use when

            
            attaching the JVM software to a debugger, specify `address=`port-number.


            You can include additional options. A list of JPDA debugging options is

            
            available at

            
            `http://java.sun.com/javase/technologies/core/toolsapis/jpda/`.


            [[beaff]][[GSDVG00103]][[generating-a-stack-trace-for-debugging]]


            Generating a Stack Trace for Debugging

            
            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


            To generate a Java stack trace for debugging, use the

            
            `asadmin generate-jvm-report --type=thread` command. The stack trace

            
            goes to the domain-dir`/logs/server.log` file and also appears on the

            
            command prompt screen. For more information about the

            
            `asadmin generate-jvm-report` command, see the link:../reference-manual/toc.html#GSRFM[GlassFish

            
            Server Open Source Edition Reference Manual].


            [[gekvq]][[GSDVG00104]][[application-client-debugging]]


            Application Client Debugging

            
            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~


            When the `appclient` script executes the `java` command to run the

            
            Application Client Container (ACC), which in turn runs the client, it

            
            includes on the command line the value of the `VMARGS` environment

            
            variable. You can set this variable to any suitable value. For example:


            [source,oac_no_warn]

            
            ----

            
            VMARGS=-agentlib:transport=dt_socket,server=y,suspend=y,address=8118

            
            ----


            For debugging an application client, you should set suspend to `y` so

            
            you can connect the debugger to the client before any code has actually

            
            executed. Otherwise, the client may start running and execute past the

            
            point you want to examine.


            You should use different ports for the server and client if you are

            
            debugging both concurrently. For details about setting the port, see

            
            link:#beafe[JPDA Options].


            You can also include JVM options in the `appclient` script directly. For

            
            information about the `appclient` script, see the link:../reference-manual/toc.html#GSRFM[GlassFish

            
            Server Open Source Edition Reference Manual].


            [NOTE]

            
            =======================================================================


            The Application Client Container is supported only in the full GlassFish

            
            Server, not in the Web Profile. See

            
            link:java-clients.html#beakt[Developing Java Clients].


            =======================================================================


            [[beafk]][[GSDVG00105]][[open-message-queue-debugging]]


            Open Message Queue Debugging

            
            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~


            Open Message Queue has a broker logger, which can be useful for

            
            debugging Java Message Service (JMS) applications, including

            
            message-driven bean applications. You can adjust the logger's verbosity,

            
            and you can send the logger output to the broker's console using the

            
            broker's `-tty` option. For more information, see the link:../../openmq/mq-admin-guide/toc.html#GMADG[Open

            
            Message Queue Administration Guide].


            [NOTE]

            
            =======================================================================


            JMS resources are supported only in the full GlassFish Server, not in

            
            the Web Profile. See link:jms.html#beaob[Using the Java Message Service].


            =======================================================================


            [[beafl]][[GSDVG00106]][[enabling-verbose-mode]]


            Enabling Verbose Mode

            
            ~~~~~~~~~~~~~~~~~~~~~


            To have the server logs and messages printed to `System.out` on your

            
            command prompt screen, you can start the server in verbose mode. This

            
            makes it easy to do simple debugging using print statements, without

            
            having to view the `server.log` file every time.


            To start the server in verbose mode, use the `--verbose` option as

            
            follows:


            [source,oac_no_warn]

            
            ----

            
            asadmin start-domain --verbose [domain-name]

            
            ----


            When the server is in verbose mode, messages are logged to the console

            
            or terminal window in addition to the log file. In addition, pressing

            
            Ctrl-C stops the server and pressing Ctrl-\ (on UNIX platforms) or

            
            Ctrl-Break (on Windows platforms) prints a thread dump. On UNIX

            
            platforms, you can also print a thread dump using the `jstack` command

            
            (see

            
            `http://docs.oracle.com/javase/8/docs/technotes/tools/share/jstack.html`)

            
            or the command `kill -QUIT` process_id.


            [[gkpdk]][[GSDVG00107]][[class-loader-debugging]]


            Class Loader Debugging

            
            ~~~~~~~~~~~~~~~~~~~~~~


            To generate class loading messages, use the following

            
            `asadmin create-jvm-options` command:


            [source,oac_no_warn]

            
            ----

            
            asadmin create-jvm-options -verbose\:class

            
            ----


            To send the JVM messages to a special JVM log file instead of `stdout`,

            
            use the following `asadmin create-jvm-options` commands:


            [source,oac_no_warn]

            
            ----

            
            asadmin create-jvm-options -XX\:+LogVMOutput

            
            asadmin create-jvm-options -XX\:LogFile=${com.sun.aas.instanceRoot}/logs/jvm.log

            
            ----


            [NOTE]

            
            =======================================================================


            These `-XX` options are specific to the OpenJDK (or Hotspot) JVM and do

            
            not work with the JRockit JVM.


            =======================================================================


            To send the GlassFish Server messages to the Administration Console

            
            instead of `stderr`, start the domain in verbose mode as described in

            
            link:#beafl[Enabling Verbose Mode].


            [[beafm]][[GSDVG00108]][[glassfish-server-logging]]


            GlassFish Server Logging

            
            ~~~~~~~~~~~~~~~~~~~~~~~~


            You can use the GlassFish Server's log files to help debug your

            
            applications. Use the Administration Console. Select the Stand-Alone

            
            Instances component, select the instance from the table, then click the

            
            View Log Files button in the General Information page. Or select the

            
            Cluster component, select the cluster from the table, select the

            
            Instances tab, select the instance from the table, then click the View

            
            Log Files button in the General Information page.


            To change logging settings, select Logger Settings under the relevant

            
            configuration.


            For details about logging, click the Help button in the Administration

            
            Console.


            [[beafn]][[GSDVG00109]][[profiling-tools]]


            Profiling Tools

            
            ~~~~~~~~~~~~~~~


            You can use a profiler to perform remote profiling on the GlassFish

            
            Server to discover bottlenecks in server-side performance. This section

            
            describes how to configure profilers for use with GlassFish Server.


            The following topics are addressed here:


            * link:#gcicc[The NetBeans Profiler]

            
            * link:#beafo[The HPROF Profiler]

            
            * link:#beafr[The JProbe Profiler]


            Information about comprehensive monitoring and management support in the

            
            Java 2 Platform, Standard Edition ( J2SE platform) is available at

            
            `http://docs.oracle.com/javase/8/docs/technotes/guides/management/index.html`.


            [[gcicc]][[GSDVG00345]][[the-netbeans-profiler]]


            The NetBeans Profiler

            
            ^^^^^^^^^^^^^^^^^^^^^


            For information on how to use the NetBeans profiler, see

            
            `http://profiler.netbeans.org/index.html`.


            [[beafo]][[GSDVG00346]][[the-hprof-profiler]]


            The HPROF Profiler

            
            ^^^^^^^^^^^^^^^^^^


            The Heap and CPU Profiling Agent (HPROF) is a simple profiler agent

            
            shipped with the Java 2 SDK. It is a dynamically linked library that

            
            interacts with the Java Virtual Machine Profiler Interface (JVMPI) and

            
            writes out profiling information either to a file or to a socket in

            
            ASCII or binary format.


            HPROF can monitor CPU usage, heap allocation statistics, and contention

            
            profiles. In addition, it can also report complete heap dumps and states

            
            of all the monitors and threads in the Java virtual machine. For more

            
            details on the HPROF profiler, see the technical article at

            
            `http://java.sun.com/developer/technicalArticles/Programming/HPROF.html`.


            After HPROF is enabled using the following instructions, its libraries

            
            are loaded into the server process.


            [[fvylg]][[GSDVG00050]][[to-use-hprof-profiling-on-unix]]


            To Use HPROF Profiling on UNIX

            
            ++++++++++++++++++++++++++++++


            1.  Use the Administration Console. Select the JVM Settings component

            
            under the relevant configuration. Then select the Profiler tab.

            
            2.  Edit the following fields:

            
            * Profiler Name - `hprof`

            
            * Profiler Enabled - `true`

            
            * Classpath - (leave blank)

            
            * Native Library Path - (leave blank)

            
            * JVM Option - Select Add, type the HPROF JVM option in the Value field,

            
            then check its box. The syntax of the HPROF JVM option is as follows: +

            
            [source,oac_no_warn]

            
            ----

            
            -Xrunhprof[:help]|[:param=value,param2=value2, ...]

            
            ----

            
            Here is an example of params you can use: +

            
            [source,oac_no_warn]

            
            ----

            
            -Xrunhprof:file=log.txt,thread=y,depth=3

            
            ----

            
            The file parameter determines where the stack dump is written. +

            
            Using help lists parameters that can be passed to HPROF. The output is

            
            as follows: +

            
            [source,oac_no_warn]

            
            ----

            
            Hprof usage: -Xrunhprof[:help]|[:<option>=<value>, ...]


            Option Name and Value   Description             Default

            
            ---------------------   -----------             -------

            
            heap=dump|sites|all     heap profiling          all

            
            cpu=samples|old         CPU usage               off

            
            format=a|b              ascii or binary output  a

            
            file=<file>             write data to file      java.hprof

            
                                           (.txt for ascii)

            
            net=<host>:<port>       send data over a socket write to file

            
            depth=<size>            stack trace depth       4

            
            cutoff=<value>          output cutoff point     0.0001

            
            lineno=y|n              line number in traces?  y

            
            thread=y|n              thread in traces?       n

            
            doe=y|n                 dump on exit?           y

            
            ----

            
            ::


            [NOTE]

            
            =======================================================================


            Do not use help in the JVM Option field. This parameter prints text to

            
            the standard output and then exits.


            The help output refers to the parameters as options, but they are not

            
            the same thing as JVM options.


            =======================================================================


            3.  [[hprofstp2]] +

            
            Restart the GlassFish Server. +

            
            This writes an HPROF stack dump to the file you specified using the file

            
            HPROF parameter.


            [[beafr]][[GSDVG00347]][[the-jprobe-profiler]]


            The JProbe Profiler

            
            ^^^^^^^^^^^^^^^^^^^


            Information about JProbe from Sitraka is available at

            
            `http://www.quest.com/jprobe/`.


            After JProbe is installed using the following instructions, its

            
            libraries are loaded into the server process.


            [[fvymj]][[GSDVG00051]][[to-enable-remote-profiling-with-jprobe]]


            To Enable Remote Profiling With JProbe

            
            ++++++++++++++++++++++++++++++++++++++


            1.  Install JProbe 3.0.1.1. +

            
            For details, see the JProbe documentation.

            
            2.  Configure GlassFish Server using the Administration Console:

            
            1.  Select the JVM Settings component under the relevant configuration.

            
            Then select the Profiler tab.

            
            2.  Edit the following fields before selecting Save and restarting the

            
            server: +

            
            Profiler Name - `jprobe` +

            
            Profiler Enabled - `true` +

            
            Classpath - (leave blank) +

            
            Native Library Path - JProbe-dir`/profiler` +

            
            JVM Option - For each of these options, select Add, type the option in

            
            the Value field, then check its box: +

            
            [source,oac_no_warn]

            
            ----

            
                -Xbootclasspath/p:JProbe-dir/profiler/jpagent.jar

            
                -Xrunjprobeagent

            
                -Xnoclassgc

            
            ----

            
            ::


            [NOTE]

            
            =======================================================================


            If any of the configuration options are missing or incorrect, the

            
            profiler might experience problems that affect the performance of the

            
            GlassFish Server.


            =======================================================================


            When the server starts up with this configuration, you can attach the

            
            profiler.

            
            3.  Set the following environment variable: +

            
            [source,oac_no_warn]

            
            ----

            
            JPROBE_ARGS_0=-jp_input=JPL-file-path

            
            ----

            
            See Step link:#jprbstp6[6] for instructions on how to create the JPL

            
            file.

            
            4.  Start the server instance.

            
            5.  Launch the `jpprofiler` and attach to Remote Session. The default

            
            port is `4444`.

            
            6.  [[jprbstp6]] +

            
            Create the JPL file using the JProbe Launch Pad. Here are the required

            
            settings:

            
            1.  Select Server Side for the type of application.

            
            2.  On the Program tab, provide the following details: +

            
            Target Server - other-server +

            
            Server home Directory - as-install +

            
            Server class File - `com.sun.enterprise.server.J2EERunner` +

            
            Working Directory - as-install +

            
            Classpath - as-install`/lib/appserv-rt.jar` +

            
            Source File Path - source-code-dir (in case you want to get the line

            
            level details) +

            
            Server class arguments - (optional) +

            
            Main Package - `com.sun.enterprise.server` +

            
            You must also set VM, Attach, and Coverage tabs appropriately. For

            
            further details, see the JProbe documentation. After you have created

            
            the JPL file, use this an input to `JPROBE_ARGS_0`.
	type=page
	status=published
	title=Debugging Applications
	next=part-apps-and-app-comps.html
	prev=class-loaders.html
	~~~~~~
	Debugging Applications
	======================

	[[GSDVG00004]][[beafc]]


	[[debugging-applications]]
	3 Debugging Applications
	------------------------

	This chapter gives guidelines for debugging applications in the Oracle
	GlassFish Server.

	The following topics are addressed here:

	* link:#beafd[Enabling Debugging]
	* link:#beafe[JPDA Options]
	* link:#beaff[Generating a Stack Trace for Debugging]
	* link:#gekvq[Application Client Debugging]
	* link:#beafk[Open Message Queue Debugging]
	* link:#beafl[Enabling Verbose Mode]
	* link:#gkpdk[Class Loader Debugging]
	* link:#beafm[GlassFish Server Logging]
	* link:#beafn[Profiling Tools]

	[[beafd]][[GSDVG00101]][[enabling-debugging]]

	Enabling Debugging
	~~~~~~~~~~~~~~~~~~

	When you enable debugging, you enable both local and remote debugging.
	To start the server in debug mode, use the `--debug` option as follows:

	[source,oac_no_warn]
	----
	asadmin start-domain --debug [domain-name]
	----

	You can then attach to the server from the Java Debugger (`jdb`) at its
	default Java Platform Debugger Architecture (JPDA) port, which is 9009.
	For example, for UNIX systems:

	[source,oac_no_warn]
	----
	jdb -attach 9009
	----

	For Windows:

	[source,oac_no_warn]
	----
	jdb -connect com.sun.jdi.SocketAttach:port=9009
	----

	For more information about the `jdb` debugger, see the following links:

	* Java Platform Debugger Architecture - The Java Debugger:
	`http://java.sun.com/javase/technologies/core/toolsapis/jpda/`
	* Java Platform Debugger Architecture - Connecting with JDB:
	`http://java.sun.com/javase/technologies/core/toolsapis/jpda/`

	GlassFish Server debugging is based on the JPDA. For more information,
	see link:#beafe[JPDA Options].

	You can attach to the GlassFish Server using any JPDA compliant
	debugger, including that of http://www.netbeans.org[NetBeans]
	(`http://www.netbeans.org`), Java Studio Enterprise, JBuilder, Eclipse,
	and so on.

	You can enable debugging even when the GlassFish Server is started
	without the `--debug` option. This is useful if you start the GlassFish
	Server from the Windows Start Menu, or if you want to make sure that
	debugging is always turned on.

	[[fvyit]][[GSDVG00049]][[to-set-the-server-to-automatically-start-up-in-debug-mode]]

	To Set the Server to Automatically Start Up in Debug Mode
	^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

	1. Use the Administration Console. Select the JVM Settings component
	under the relevant configuration.
	2. Check the Debug Enabled box.
	3. To specify a different port (from 9009, the default) to use when
	attaching the JVM software to a debugger, specify `address=` port-number
	in the Debug Options field.
	4. To add JPDA options, add any desired JPDA debugging options in Debug
	Options. See link:#beafe[JPDA Options].

	[[GSDVG532]]

	See Also

	For details, click the Help button in the Administration Console from
	the JVM Settings page.

	[[beafe]][[GSDVG00102]][[jpda-options]]

	JPDA Options
	~~~~~~~~~~~~

	The default JPDA options in GlassFish Server are as follows:

	[source,oac_no_warn]
	----
	-Xdebug -agentlib:transport=dt_socket,server=y,suspend=n,address=9009
	----

	For Windows, you can change `dt_socket` to `dt_shmem`.

	If you substitute `suspend=y`, the JVM software starts in suspended mode
	and stays suspended until a debugger attaches to it. This is helpful if
	you want to start debugging as soon as the JVM software starts.

	To specify a different port (from 9009, the default) to use when
	attaching the JVM software to a debugger, specify `address=`port-number.

	You can include additional options. A list of JPDA debugging options is
	available at
	`http://java.sun.com/javase/technologies/core/toolsapis/jpda/`.

	[[beaff]][[GSDVG00103]][[generating-a-stack-trace-for-debugging]]

	Generating a Stack Trace for Debugging
	~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	To generate a Java stack trace for debugging, use the
	`asadmin generate-jvm-report --type=thread` command. The stack trace
	goes to the domain-dir`/logs/server.log` file and also appears on the
	command prompt screen. For more information about the
	`asadmin generate-jvm-report` command, see the link:../reference-manual/toc.html#GSRFM[GlassFish
	Server Open Source Edition Reference Manual].

	[[gekvq]][[GSDVG00104]][[application-client-debugging]]

	Application Client Debugging
	~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	When the `appclient` script executes the `java` command to run the
	Application Client Container (ACC), which in turn runs the client, it
	includes on the command line the value of the `VMARGS` environment
	variable. You can set this variable to any suitable value. For example:

	[source,oac_no_warn]
	----
	VMARGS=-agentlib:transport=dt_socket,server=y,suspend=y,address=8118
	----

	For debugging an application client, you should set suspend to `y` so
	you can connect the debugger to the client before any code has actually
	executed. Otherwise, the client may start running and execute past the
	point you want to examine.

	You should use different ports for the server and client if you are
	debugging both concurrently. For details about setting the port, see
	link:#beafe[JPDA Options].

	You can also include JVM options in the `appclient` script directly. For
	information about the `appclient` script, see the link:../reference-manual/toc.html#GSRFM[GlassFish
	Server Open Source Edition Reference Manual].


	[NOTE]
	=======================================================================

	The Application Client Container is supported only in the full GlassFish
	Server, not in the Web Profile. See
	link:java-clients.html#beakt[Developing Java Clients].

	=======================================================================


	[[beafk]][[GSDVG00105]][[open-message-queue-debugging]]

	Open Message Queue Debugging
	~~~~~~~~~~~~~~~~~~~~~~~~~~~~

	Open Message Queue has a broker logger, which can be useful for
	debugging Java Message Service (JMS) applications, including
	message-driven bean applications. You can adjust the logger's verbosity,
	and you can send the logger output to the broker's console using the
	broker's `-tty` option. For more information, see the link:../../openmq/mq-admin-guide/toc.html#GMADG[Open
	Message Queue Administration Guide].


	[NOTE]
	=======================================================================

	JMS resources are supported only in the full GlassFish Server, not in
	the Web Profile. See link:jms.html#beaob[Using the Java Message Service].

	=======================================================================


	[[beafl]][[GSDVG00106]][[enabling-verbose-mode]]

	Enabling Verbose Mode
	~~~~~~~~~~~~~~~~~~~~~

	To have the server logs and messages printed to `System.out` on your
	command prompt screen, you can start the server in verbose mode. This
	makes it easy to do simple debugging using print statements, without
	having to view the `server.log` file every time.

	To start the server in verbose mode, use the `--verbose` option as
	follows:

	[source,oac_no_warn]
	----
	asadmin start-domain --verbose [domain-name]
	----

	When the server is in verbose mode, messages are logged to the console
	or terminal window in addition to the log file. In addition, pressing
	Ctrl-C stops the server and pressing Ctrl-\ (on UNIX platforms) or
	Ctrl-Break (on Windows platforms) prints a thread dump. On UNIX
	platforms, you can also print a thread dump using the `jstack` command
	(see
	`http://docs.oracle.com/javase/8/docs/technotes/tools/share/jstack.html`)
	or the command `kill -QUIT` process_id.

	[[gkpdk]][[GSDVG00107]][[class-loader-debugging]]

	Class Loader Debugging
	~~~~~~~~~~~~~~~~~~~~~~

	To generate class loading messages, use the following
	`asadmin create-jvm-options` command:

	[source,oac_no_warn]
	----
	asadmin create-jvm-options -verbose\:class
	----

	To send the JVM messages to a special JVM log file instead of `stdout`,
	use the following `asadmin create-jvm-options` commands:

	[source,oac_no_warn]
	----
	asadmin create-jvm-options -XX\:+LogVMOutput
	asadmin create-jvm-options -XX\:LogFile=${com.sun.aas.instanceRoot}/logs/jvm.log
	----


	[NOTE]
	=======================================================================

	These `-XX` options are specific to the OpenJDK (or Hotspot) JVM and do
	not work with the JRockit JVM.

	=======================================================================


	To send the GlassFish Server messages to the Administration Console
	instead of `stderr`, start the domain in verbose mode as described in
	link:#beafl[Enabling Verbose Mode].

	[[beafm]][[GSDVG00108]][[glassfish-server-logging]]

	GlassFish Server Logging
	~~~~~~~~~~~~~~~~~~~~~~~~

	You can use the GlassFish Server's log files to help debug your
	applications. Use the Administration Console. Select the Stand-Alone
	Instances component, select the instance from the table, then click the
	View Log Files button in the General Information page. Or select the
	Cluster component, select the cluster from the table, select the
	Instances tab, select the instance from the table, then click the View
	Log Files button in the General Information page.

	To change logging settings, select Logger Settings under the relevant
	configuration.

	For details about logging, click the Help button in the Administration
	Console.

	[[beafn]][[GSDVG00109]][[profiling-tools]]

	Profiling Tools
	~~~~~~~~~~~~~~~

	You can use a profiler to perform remote profiling on the GlassFish
	Server to discover bottlenecks in server-side performance. This section
	describes how to configure profilers for use with GlassFish Server.

	The following topics are addressed here:

	* link:#gcicc[The NetBeans Profiler]
	* link:#beafo[The HPROF Profiler]
	* link:#beafr[The JProbe Profiler]

	Information about comprehensive monitoring and management support in the
	Java 2 Platform, Standard Edition ( J2SE platform) is available at
	`http://docs.oracle.com/javase/8/docs/technotes/guides/management/index.html`.

	[[gcicc]][[GSDVG00345]][[the-netbeans-profiler]]

	The NetBeans Profiler
	^^^^^^^^^^^^^^^^^^^^^

	For information on how to use the NetBeans profiler, see
	`http://profiler.netbeans.org/index.html`.

	[[beafo]][[GSDVG00346]][[the-hprof-profiler]]

	The HPROF Profiler
	^^^^^^^^^^^^^^^^^^

	The Heap and CPU Profiling Agent (HPROF) is a simple profiler agent
	shipped with the Java 2 SDK. It is a dynamically linked library that
	interacts with the Java Virtual Machine Profiler Interface (JVMPI) and
	writes out profiling information either to a file or to a socket in
	ASCII or binary format.

	HPROF can monitor CPU usage, heap allocation statistics, and contention
	profiles. In addition, it can also report complete heap dumps and states
	of all the monitors and threads in the Java virtual machine. For more
	details on the HPROF profiler, see the technical article at
	`http://java.sun.com/developer/technicalArticles/Programming/HPROF.html`.

	After HPROF is enabled using the following instructions, its libraries
	are loaded into the server process.

	[[fvylg]][[GSDVG00050]][[to-use-hprof-profiling-on-unix]]

	To Use HPROF Profiling on UNIX
	++++++++++++++++++++++++++++++

	1. Use the Administration Console. Select the JVM Settings component
	under the relevant configuration. Then select the Profiler tab.
	2. Edit the following fields:
	* Profiler Name - `hprof`
	* Profiler Enabled - `true`
	* Classpath - (leave blank)
	* Native Library Path - (leave blank)
	* JVM Option - Select Add, type the HPROF JVM option in the Value field,
	then check its box. The syntax of the HPROF JVM option is as follows: +
	[source,oac_no_warn]
	----
	-Xrunhprof[:help]\|[:param=value,param2=value2, ...]
	----
	Here is an example of params you can use: +
	[source,oac_no_warn]
	----
	-Xrunhprof:file=log.txt,thread=y,depth=3
	----
	The file parameter determines where the stack dump is written. +
	Using help lists parameters that can be passed to HPROF. The output is
	as follows: +
	[source,oac_no_warn]
	----
	Hprof usage: -Xrunhprof[:help]\|[:<option>=<value>, ...]

	Option Name and Value Description Default
	--------------------- ----------- -------
	heap=dump\|sites\|all heap profiling all
	cpu=samples\|old CPU usage off
	format=a\|b ascii or binary output a
	file=<file> write data to file java.hprof
	(.txt for ascii)
	net=<host>:<port> send data over a socket write to file
	depth=<size> stack trace depth 4
	cutoff=<value> output cutoff point 0.0001
	lineno=y\|n line number in traces? y
	thread=y\|n thread in traces? n
	doe=y\|n dump on exit? y
	----
	::

	[NOTE]
	=======================================================================

	Do not use help in the JVM Option field. This parameter prints text to
	the standard output and then exits.

	The help output refers to the parameters as options, but they are not
	the same thing as JVM options.

	=======================================================================

	3. [[hprofstp2]] +
	Restart the GlassFish Server. +
	This writes an HPROF stack dump to the file you specified using the file
	HPROF parameter.

	[[beafr]][[GSDVG00347]][[the-jprobe-profiler]]

	The JProbe Profiler
	^^^^^^^^^^^^^^^^^^^

	Information about JProbe from Sitraka is available at
	`http://www.quest.com/jprobe/`.

	After JProbe is installed using the following instructions, its
	libraries are loaded into the server process.

	[[fvymj]][[GSDVG00051]][[to-enable-remote-profiling-with-jprobe]]

	To Enable Remote Profiling With JProbe
	++++++++++++++++++++++++++++++++++++++

	1. Install JProbe 3.0.1.1. +
	For details, see the JProbe documentation.
	2. Configure GlassFish Server using the Administration Console:
	1. Select the JVM Settings component under the relevant configuration.
	Then select the Profiler tab.
	2. Edit the following fields before selecting Save and restarting the
	server: +
	Profiler Name - `jprobe` +
	Profiler Enabled - `true` +
	Classpath - (leave blank) +
	Native Library Path - JProbe-dir`/profiler` +
	JVM Option - For each of these options, select Add, type the option in
	the Value field, then check its box: +
	[source,oac_no_warn]
	----
	-Xbootclasspath/p:JProbe-dir/profiler/jpagent.jar
	-Xrunjprobeagent
	-Xnoclassgc
	----
	::

	[NOTE]
	=======================================================================

	If any of the configuration options are missing or incorrect, the
	profiler might experience problems that affect the performance of the
	GlassFish Server.

	=======================================================================

	When the server starts up with this configuration, you can attach the
	profiler.
	3. Set the following environment variable: +
	[source,oac_no_warn]
	----
	JPROBE_ARGS_0=-jp_input=JPL-file-path
	----
	See Step link:#jprbstp6[6] for instructions on how to create the JPL
	file.
	4. Start the server instance.
	5. Launch the `jpprofiler` and attach to Remote Session. The default
	port is `4444`.
	6. [[jprbstp6]] +
	Create the JPL file using the JProbe Launch Pad. Here are the required
	settings:
	1. Select Server Side for the type of application.
	2. On the Program tab, provide the following details: +
	Target Server - other-server +
	Server home Directory - as-install +
	Server class File - `com.sun.enterprise.server.J2EERunner` +
	Working Directory - as-install +
	Classpath - as-install`/lib/appserv-rt.jar` +
	Source File Path - source-code-dir (in case you want to get the line
	level details) +
	Server class arguments - (optional) +
	Main Package - `com.sun.enterprise.server` +
	You must also set VM, Attach, and Coverage tabs appropriately. For
	further details, see the JProbe documentation. After you have created
	the JPL file, use this an input to `JPROBE_ARGS_0`.