BTrace is a safe, dynamic tracing tool for understanding live Java applications. It instruments a running JVM temporarily, so you can answer a focused question without changing application code or restarting the process.

Latest stable release: BTrace 2.2.6.

For the latest stable release, attach a Java probe:

btrace <PID> MyTrace.java

Stable 2.2.x probes use the org.openjdk.btrace namespace.

• Getting Started — installation and attach workflow.
• Documentation — guides and reference for the stable release.
• Troubleshooting — attachment, verification, and performance troubleshooting.

JFR provides continuous, low-overhead history. BTrace can be used alongside JFR for targeted observations while diagnosing a live application.

• Source and releases
• Issues
• Security policy