"Analyzing Crashed JVMs" [IJN]

About this episode

This episode discusses the jcmd tool for analyzing JVMs and the potential of JEP 528 for extracting information from crashed JVMs.

The Java tool jcmd ("j command") sends diagnostic commands to the JVM, which will react by supplying the desired information: from finalizer queues to heap and thread dumps, from GC insights to virtual thread scheduler statistics. At the moment, this requires a running JVM, but once candidate JEP 528 is adopted, a lot of that information can be seamlessly extracted from a crashed JVM's core dump, allowing easy post-mortem analysis.

People in this episode

Host: David Delabassee

Topics covered

• JVM analysis
• jcmd tool
• core dump
• post-mortem analysis
• Java
• diagnostic commands

Keywords

• jcmd
• JVM
• core dump
• JEP 528
• diagnostic commands
• heap dump
• thread dump
• GC insights

Mentioned in this episode

Organizations: JVM

Products: jcmd

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