Heap dump error on Centos 64bit and openjdk 7

This may be related, but on some Java versions, there seems to be a slight oddity on recent RHEL / Centos (version >= 6) whereby jmap, jstack and friends need to be run as the exact user that started the process - and it will not work if run as root.

A command like:

sudo -H -u <USERNAME WHO STARTED PROCESS> jmap -histo <PID>

should take care of it, assuming you have appropriate sudo privileges.

Posting this so I dont keep forgetting the solution myself :P

This works:

$ sudo /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.51.x86_64/bin/jmap -dump:format=b,file=./testDump   8894
Dumping heap to /home/<snip>/testDump ...
Heap dump file created

This fails:

$ sudo /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.51.x86_64/bin/jmap -heap:format=b     8894
Attaching to process ID 8894, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 24.45-b08
Dumping heap to heap.bin ...
Exception in thread "main" java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at     sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at sun.tools.jmap.JMap.runTool(JMap.java:197)
at sun.tools.jmap.JMap.main(JMap.java:128)
Caused by: sun.jvm.hotspot.utilities.AssertionFailure: Expecting GenCollectedHeap, G1CollectedHeap, or ParallelScavengeHeap, but got sun.jvm.hotspot.gc_interface.CollectedHeap
at sun.jvm.hotspot.utilities.Assert.that(Assert.java:32)
at sun.jvm.hotspot.oops.ObjectHeap.collectLiveRegions(ObjectHeap.java:604)
at sun.jvm.hotspot.oops.ObjectHeap.iterate(ObjectHeap.java:244)
at sun.jvm.hotspot.utilities.AbstractHeapGraphWriter.write(AbstractHeapGraphWriter.java:51)
at sun.jvm.hotspot.utilities.HeapHprofBinWriter.write(HeapHprofBinWriter.java:416)
at sun.jvm.hotspot.tools.HeapDumper.run(HeapDumper.java:56)
at sun.jvm.hotspot.tools.Tool.start(Tool.java:221)
at sun.jvm.hotspot.tools.HeapDumper.main(HeapDumper.java:77)
... 6 more

Try running without the -F option