I navigated to https://chromiumdash.appspot.com/components/Internals/Metrics/UMA and triaged some bugs, then refreshed the page (and navigated back to the component, but that's  bug 757559 ). I saw that the data on the page did not update to reflect my triaging. That's ok -- we don't necessarily need live updates -- but it would be nice if the dashboard gave an indication of how often the data is updated!