In RHQ and JBossON 2, that is built on top of RHQ,
you have the possibility to graph metrics for (more or less) arbitrary time ranges.
But sometimes the display is not moving and not showing any data that you'd expect to see.
If this is the case, have a look at the time range setting, which are below the graphs:
Here it is fixed to a 1 hour interval between 10:31am on jun 16th to 11:31am on the same day.
This means that RHQ will all over the place only show metric data for this 1 hour timerange.
To get things "dynamic" again, just select the "Last x hours" radio button and click on "redraw".