My setup seems to have a lot of regions with no data that just keep accumulating over time. Here are some details:
I have time-series data (created by opentsdb) being inserted into hbase every minute. Since the data has little value after say 15 days, I go ahead and delete all old data. When I look at /regionserver.jsp, I see a lot of regions being listed that I know has no data. To confirm this hypothesis, I ran a query on the shell with the start and end key of a given region and I get zero rows: http://pastebin.ca/2072627 . The value of the start & end row is something that the regionservier reported for a specific region. I've run this test over multiple regions that I suspected to have zero rows and I get the same behaviour. Explicitly running a major compaction does not seem to help either. So my question is that once a region is created, does it live forever even if there are zero rows present in that region? I ask because I am worried that the master is having to carry the burden of empty regions as time passes and the list will just keep building forever.
