Performance analysis tool for the Java Runtime Environment.


Lightweight and low overhead.

Exposes key performance metrics from the Java runtime.


Top4J Top Threads Top4J Top Threads Linux Top4J is a lightweight, low overhead, production-ready performance analysis tool for the Java Runtime Environment. As the name suggests, it works a bit like the UNIX/Linux top command but at the JVM-level exposing key performance metrics from a Java runtime perspective.

Top4J has two modes of operation: Remote Attach command-line interface (CLI) and Java Agent.

The Top4J Remote Attach function is executed via the command line and attaches to a remote JVM process via the JDK tools VirtualMachine API.

The Top4J Java Agent is invoked via the standard "java -javaagent" command line argument and runs as a background thread inside the target JVM.

Top4J is free to download and use under the terms of the Apache 2.0 License.

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