Jboss heap dump

Jboss Heap Dump

Heap dumps are used for debugging memory issues in Java applications. A heap dump essentially captures the entire memory state of a Java process at a given point in time, including all objects and their references. Analyzing a heap dump can help identify memory leaks, excessive memory usage, and other issues.

How to generate a heap dump in JBoss

There are multiple ways to generate a heap dump in JBoss. Here are a few:

• Using JMX console: The JBoss JMX console provides an easy way to generate heap dumps. Simply navigate to the MBean tab, select the jboss.system:type=ServerInfo MBean, and click on the heapDump operation. This will generate a heap dump file in the JBoss server's bin directory.
• Using jmap: The jmap utility can be used to generate heap dumps from the command line. First, get the process ID of the JBoss server using the jps command. Then, run the following command:

jmap -dump:format=b,file=/path/to/dumpfile 

This will generate a binary-format heap dump file.

• Using jcmd: Java 7 introduced the jcmd utility, which can be used to generate heap dumps as well. First, get the process ID of the JBoss server using the jcmd command. Then, run the following command:

jcmd  GC.heap_dump /path/to/dumpfile

This will generate a binary-format heap dump file.

How to analyze a heap dump

Analyzing a heap dump can be a complex task, but there are tools available that can make it easier. One popular tool is Eclipse Memory Analyzer (MAT), which is a free and open-source tool that can analyze heap dumps from Java applications.

To analyze a heap dump using MAT, simply open the heap dump file in the tool. MAT will generate a report that includes information on memory usage, object sizes, and more. You can use this information to identify memory leaks, excessive memory usage, and other issues.

Overall, generating and analyzing heap dumps can be a valuable tool for debugging memory issues in JBoss applications.