"warnIfOSX Loading the SizeOfAgent will probably fail, as you are running on Apple OS X and have a value set for java.io.tmpdir
They both result in a bug, not yet fixed by Apple, that won't let us attach to the VM and load the agent.
Most probably, you'll also get a full thread-dump after this because of the failure... Nothing to worry about! "
I found it in confluence logs . Don't worry ,it is just another bug not yet fixed by Apple!