I have Java application, which, unfortunately, begins to consume quite big amounts of memory after some time. To complicate things, it's not only Java application, it is also JavaFX 2 application.
I suspect that there is some memory leak, maybe even in underlying JavaFX calls and native libs.
The ideal solution would be to get a dump of all java objects at some moment (with their memory usage), and then analyze that dump. Is there some way to achieve this?
I just re-discovered this article when researching ways to grab "JVM state right at this moment" - after a heap I pulled with jmap was about half the size of what the MBeans reported. I'll add it for completeness:
su $JVM_OWNER -c "gcore -o /tmp/jvm.core $YOUR_JVM_PID"
su $JVM_OWNER -c "jmap -dump:format=b,file=jvm.hprof /usr/bin/java /tmp/jvm.core"
Requires gdb installed (for gcore) and a JDK installation (for jmap). Also note you'd might need to adjust /usr/bin/java to the path of the JVM used for the process.