Java Management Extensions (JMX) is a Java technology that allows administrators to monitor and manage Java applications. JStat is a Java tool that is used to monitor Java Virtual Machines (JVMs). JStat is included in the Java Development Kit (JDK) and it can be used to monitor JVMs running on Linux, Windows, and macOS.

How to Find JStat on Linux

There are a few different ways to find JStat on Linux.

1. Use the which Command

One way to find JStat is to use the which command. The which command will search your system for a specified command and tell you where it is located. To use the which command to find JStat, open a terminal window and type the following command:

which jstat

If JStat is installed, the which command will output the path to the JStat executable. For example, the following output shows that JStat is located at /usr/bin/jstat:

/usr/bin/jstat

2. Use the find Command

Another way to find JStat is to use the find command. The find command will search your system for a specified file or directory. To use the find command to find JStat, open a terminal window and type the following command:

find / -name jstat

This command will search the entire / directory tree for a file named jstat. If JStat is installed, the find command will output the path to the JStat executable. For example, the following output shows that JStat is located at /usr/bin/jstat:

/usr/bin/jstat

3. Search the JDK Installation Directory

You can also find JStat by searching the JDK installation directory. The JDK installation directory is typically located at /usr/java/jdk<version>, where <version> is the version of the JDK that you have installed. To find JStat in the JDK installation directory, open a terminal window and type the following command:

locate jstat

This command will search the JDK installation directory for a file named jstat. If JStat is installed, the locate command will output the path to the JStat executable. For example, the following output shows that JStat is located at /usr/java/jdk1.8.0_201/bin/jstat:

/usr/java/jdk1.8.0_201/bin/jstat

How to Use JStat

Once you have found JStat, you can use it to monitor JVMs running on your system. To use JStat, open a terminal window and type the following command:

jstat <options> <pid>

where:

• <options> are the options that you want to use with JStat. For example, you can use the -gc option to monitor garbage collection.
• <pid> is the process ID of the JVM that you want to monitor.

For example, the following command uses the -gc option to monitor garbage collection in the JVM with the process ID 1234:

jstat -gc 1234

JStat will then output a table of information about the JVM's garbage collection activity.

Conclusion

JStat is a powerful tool that can be used to monitor Java Virtual Machines (JVMs) running on Linux. By following the steps in this article, you can easily find and use JStat to monitor your JVMs.

FAQs

1. What is JStat?

JStat is a Java tool that is used to monitor Java Virtual Machines (JVMs).

2. How can I find JStat on Linux?

You can find JStat on Linux by using the which, find, or locate commands.

3. How can I use JStat to monitor JVMs?

To use JStat to monitor JVMs, open a terminal window and type the following command:

jstat <options> <pid>

4. What are some of the options that I can use with JStat?

There are a number of options that you can use with JStat. Some of the most common options include:

• -gc: Monitor garbage collection.
• -class: Monitor class loading.
• -compiler: Monitor the JIT compiler.
• -memory: Monitor memory usage.
• -threads: Monitor threads.

5. Where can I find more information about JStat?

You can find more information about JStat in the Oracle documentation:

https://docs.oracle.com/javase/7/docs/api/com/sun/tools/jstat/JStat.html