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Jconsole — the Graphical Monitor of Your Application
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Introducing Jconsole
jconsole — start a graphical console to monitor and manage Java applications
Synopsis
jconsole [-interval=n] [-notile] [-plugin path] [-version] [connection ... ] [-Jinput_arguments]
jconsole -help
Options
-interval
Sets the update interval to n seconds (default is 4 seconds).
-notile
Doesn’t tile the windows for two or more connections.
-pluginpath path
Specifies the path that jconsole uses to look up plug-ins. The plug-in path should contain a provider-configuration file named META-INF/services/com.sun.tools.jconsole.JConsolePlugin that contains one line for each plug-in. The line specifies the fully qualified class name of the class implementing the com.sun.tools.jconsole.JConsolePlugin class.
-version
Prints the program version.
connection = pid | host:port | jmxURL
A connection is described by either pid, host:port or jmxURL.
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The pid value is the process ID of a target process. The JVM must be running with the same user ID as the user ID running the
jconsolecommand. -
The host
:port values are the name of the host system on which the JVM is running, and the port number specified by the system propertycom.sun.management.jmxremote.portwhen the JVM was started. -
The jmxUrl value is the address of the JMX agent to be connected to as described in JMXServiceURL.
-Jinput_arguments
Passes input_arguments to the JVM on which the jconsole command is run.
-help or --help
Displays the help message for the command.
Description
The jconsole command starts a graphical console tool that lets you monitor and manage Java applications and virtual machines on a local or remote machine.
On Windows, the jconsole command doesn’t associate with a console window. It does, however, display a dialog box with error information when the jconsole command fails.
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Jconsole — the Graphical Monitor of Your Application
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Sometimes you need to have an idea about what happens on your JVM. In fact, your need to profile and monitor your Java Virtual Machine to see how your resources are used. Three ways will be shown it this article to know how you can Profile and Monitor your Java Virtual Machine (JVM).
- JConsole
- JVisualVM
- Java Monitor on Eclipse IDE
Table of contents
- 1 1- JConsole
- 2 2- Java VisualVM
- 3 3- Monitor JVM on Eclipse IDE
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- 3.0.1 Plugin installation
- 3.0.2 Use JVM Monitor
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1- JConsole
Java offers a graphical user interface called JConsole that complies to the Java Management Extensions (JMX) specification. It gives you a good overview of what happens in your JVM (Memory, threads…). Let’s see how you can use it !
- Necessary if your are on a JDK 5
If you are using a JDK5, you need to add the property -Dcom.sun.management.jmxremote to your application to be able to use JConsole.
If you are running your server on windows, locate your server start script, for example run.bat under <YOUR_SEVRER>/bin and add this line :
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set JAVA_OPTS=%JAVA_OPTS% —Dcom.sun.management.jmxremote |
On linux server, locate your server start script, for example run.sh and add the following line :
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JAVA_OPTS=«$JAVA_OPTS -Dcom.sun.management.jmxremote» |
To run Jconsole, follow these instructions :
- Open a prompt command a tape « jconsole » or go to JDK_HOME/bin and execute jconsole.exe
- Select your application and click “Connect”
JConsole : Connecting to agent
- JConsole will open and your can monitor your JVM
Jconsole JVM monitoring
If your want to profile a remote Java Application, go the “Remote” tab, set the information of the remote server and click connect.
2- Java VisualVM
Since JDK6
Since JDK6, Java introduced « JVisualVM ». JVisualVM play the same role as jconsole but it’s much more improved with better user-friendly interface.
To run JVisualVM , follow these instructions :
- Open a prompt command a tape « jvisualvm » or go to your JDK_HOME/bin and execute jvisualvm.exe
- Java VisualVM will open. On “Applications” view, double-click on the application you want to monitor. A new tab will open where you will be able to see what happens in your jvm.
JVisualVM Monitoring
If your want to profile a remote Java Application, on “Applications” view, right-click on “Remote“, and click on “Add remote host…”, set the information of the remote server and click “Ok“.
3- Monitor JVM on Eclipse IDE
If you are using Eclipse IDE and want to monitor your JVM, you can use the free jvmmonitor plugin.
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Plugin installation
The plugin must be installed on your Eclipse IDE. Choose one of the following options :
- On Eclipse, click Help -> Eclipse Marketplace… and tape “JVM Monitor” and click Install button
- OR : Help -> Install New Software… > Add…, and enter the following update site.
http://www.jvmmonitor.org/updates/3.8
- OR : You can also manually install the plugin by download this zip file, and unzip it in $ECLIPSE_HOME/dropins folder
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Use JVM Monitor
On Eclipse, click on Window -> Open perspective -> Other and Select Java Monitor and click OK.
Opening Java monitor Perspective
Start your application and on the JVM Explorer view, select the Name/PID corresponding to your application, right click and choose “Start monitoring”
JVisualVM – Start application monitoring
On the properties view, you can use the different taps to monitor your JVM.
Java monitor plugin
References
- JVM Monitor
- JConsole
- JVisualVM
In this article we are going to elaborate the jconsole commands.
What is jconsole?
jconsole command launches a GUI tool that enables monitoring and managing Java applications(on virtual machines) on a local or remote machine.
Syntax
jconsole [option] [connection..]
In here , a connection consists of java process ID of a local JVM or Name of host on which JVM is running and the port number specified by the system property or address of the JMX agent .
So , connection = pid or host:port or jmxUrl
jconsole options:
- interval=[n] : Set the update interval to n seconds (default = 4s).
- notile : Does not tile windows initially (for two+ connections).
- pluginpath (path to plugins): Specify a list of directories or JAR files for JConsole plugins.
- J(option) : Pass option to the Java virtual machine on which jconsole is running.
Connect JVM with Jconsole
- When we start jconsole, we get the Java Monitoring & Management console with New Connection wizard. I have started jconsole from command prompt, so we can see the jconsole in local process.
We can get remote process also.
- When we connect, we get detail information viewer. ( in this example, I have connected to jconsole itself).
we can see the graphs of Memory, Threads, Classes, CPU used by VM. Detail of these information are displayed in separate tabs. We can select time range which define the display information’s time span.
In right upper corner we can see the disconnect button used for disconnect with current VM.
Memory :
In this tab we see detail memory used.
- Perform GC button performs garbage collection if we click on that. GC performs on Eden Space(heap), Survivor Space(heap), Tenured Generation(heap), Permanent Generation(non-heap), Code Cache(non-heap).
- We can see different type of memory information from selectable combo option
- In Down right, we can see Heap & Non-Heap memory info using a Bar chart.
- In Down Left , we can get detail memory info.
Threads :
In this tab we see detail Thread operations
- We can select Time span for graph
- Full running threads are shown left bottom. If we select any one of them, we can see details. Filter can be done over the list
- A Detect Deadlock button is there to find dead lock threads.
Classes :
In this tab we see running Classes
VM summary :
In this tab we see detail JVM information
MBeans :
In this tab we see about all the MBeans registered with the platform MBean server
- If we select any of items, it shows detail property values of that item running in JVM. We use this for detail information about process running in VM.
For more details visit oracle docs.
Thanks…:)
Jconsole Windows The jconsole tool is a jmx compliant graphical tool for monitoring a java virtual machine. it can monitor both local and remote jvms. it can also monitor and manage an application. see using jconsole for more information on jconsole’s functionality and the jconsole command line tool documentation for jconsole’s command line options. Jconsole 是一个内置 java 性能分析器，不需要安装。 可以使用命令行启动， 当jdk 在 path环境变量中时，在cmd命令行中运行 jconsole 即可。 如果从 gui shell 启动，找到 jdk 安装路径（比如自己环境是在d:\program files\java\jdk1.7.0 80\bin），打开 bin 文件夹，双击 jconsole。 jconsole在自己的工作电脑windows机器上，tomcat应用服务器在远程的linux系统上。 其中第一个参数可以用来设置欲连接的linux机器的ip地址，该项必须设置，否则远程连接会因为解析到127.0.0.1出现连接失败的情况（被这个问题坑的好惨）。.
Jconsole Windows The java console provides information about the java version, user home directory, and any error message that occurs while running an applet or application. learn how to enable the java console for the windows platform using the java control panel or the java icon displayed in the windows system tray. So to use jconsole for monitoring your application, you would need to compile and execute your code first and while your code is executing start > run > jconsole.exe and hit press enter. select the application which you want to monitor and then click connect. alternatively,you can use visualvm for this purpose as well. The command syntax to start jconsole for local monitoring is: jconsole [processid] where processid is the application’s process id (pid). to determine an application’s pid: on unix or linux systems, use the ps command to find the pid of java. on windows systems, use task manager to find the pid of java or javaw. Jconsole (java™ monitoring and management console) is a graphical tool that allows the user to monitor and manage the behavior of java applications. note: because jconsole consumes significant system resources, oracle recommend its use only in development environments for creating prototypes.
Jconsole Windows The command syntax to start jconsole for local monitoring is: jconsole [processid] where processid is the application’s process id (pid). to determine an application’s pid: on unix or linux systems, use the ps command to find the pid of java. on windows systems, use task manager to find the pid of java or javaw. Jconsole (java™ monitoring and management console) is a graphical tool that allows the user to monitor and manage the behavior of java applications. note: because jconsole consumes significant system resources, oracle recommend its use only in development environments for creating prototypes. Learn how to use jconsole, a graphical tool that monitors the performance and resource consumption of java applications, on windows and other platforms. find out how to start jconsole, connect to local or remote processes, and enable secure connections.
Jconsole Windows Learn how to use jconsole, a graphical tool that monitors the performance and resource consumption of java applications, on windows and other platforms. find out how to start jconsole, connect to local or remote processes, and enable secure connections.
Jconsole Windows
Jconsole Windows