I could write a VisualVM plugin for Censum but I'm not sure how much value it adds. VisualVM doesn't have visibility to the GC logs or GC logging data in general. I've already written a plugin that looks at the GC counters that are available and we're working to update that as we speak. I hope to release a new version by the end of Oct. Some people are working on adding analytics to that plugin that will make it more useful.