Major Description
I just managed to kill (hang) a region server by issuing a COUNT(DISTINCT(...)) query over a column with very high cardinality (20m in this case).
This is perhaps not a useful thing to do, but Phoenix should nonetheless not allow to have a server fail because of a query.
jamestaylor, I see there GlobalMemoryManager, but I do not quite see how I'd get a reference to one, once needs a tenant id, etc.