When using the new -Xhprof:{net,file} option when one hits ctrl-scrolllock
or ctrl-\ to take a dump the dump can take a very long time and the user
is stuck with the messgae :-
"Dumping Java heap and allocation sites ... "
Since all threads are suspended it's unclear to user if the application
is hung or if there is something really happening.

It would be nice to have a "." printed periodically while the dump file
is begin created. HAT does this when it is chasing the references and
it would be nice if -Xhprof did the same.