HeapStats

HeapStats is Java troubleshooting tool. This tool is composed of three programs:

• Agent
• HeapStats JVMTI agent for gathering JavaVM runtime information continuously.
• Analyzer
• HeapStats JavaFX GUI analyzer for analysis by various graphs.
• CLI
• HeapStats commandline analyzer.

Agent

Agent gathers various JavaVM runtime information such as the below.

• The amount of instances and total size per live object
• The reference relationship of objects on Java Heap
• Thread condition
• and more. More detailed is here.

You can attach HeapStats agent by any way of the following:

• -agentlib:heapstats[=conf]
• If libheapstats.so is located at LD_LIBRARY_PATH, you can pass -agentlib option to java.
• -agentpath:/path/to/heapstats[=conf]
• Pass libheapstats.so with -agentpath option to java.
• heapstats-attacher
• If you want to attach HeapStats to existed process, you can use this script.

If you want to set specified configuration, you can pass it to -agentlib/-agentpath after "=config file" .

Analyzer

HeapStats analyzer is GUI application for analyzing HeapStats SnapShot. You can run it on any GUI environment which has JavaFX runtime.

HeapStats analyzer supports JDP autodiscovery and Error Report Transmission.

JDP

The automatic discovery function of JDP (Java Discovery Protocol) can be enabled by the following JVM options.

-Dcom.sun.management.jmxremote.port=<JMX port>
-Dcom.sun.management.jmxremote.authenticate=<true|false>
-Dcom.sun.management.jmxremote.ssl=<true|false>
-Dcom.sun.management.jmxremote.autodiscovery=true

The JDP function sends a packet at regular intervals: 5 seconds by default. If analyzer can NOT receive a JDP packet from a monitoring JVM instance, the instance's name displayed on the screen will become orange.

Error Report Transmission

OracleJDK can provide a real-time detection of JVM crash, but OpenJDK does NOT support it. In addition, OracleJDK needs to be run with the following options.

-XX:+TransmitErrorReport
-XX:ErrorReportServer=<address>:<port (4711 by default)>

CLI

If you want to analyze HeapStats SnapShot on CUI environment, you can use HeapStats CLI.

$ java -jar heapstats-cli.jar

If you want to see details, please run heapstats-cli with -help .

Documents and Binaries

More detailed documents and released binaries are hosted at icedtea community: http://icedtea.classpath.org/wiki/HeapStats

Contributing

Contribution are most welcome! HeapStats is an open source project under the GNU General Public License, version 2. See CONTRIBUTING.md for details.

License

GNU General Public License, version 2