If a flush is happening and you bring up a cursor for a series, if that series didn't have any data in the cache (after the flush started) then it would return no data. What it should have done instead is return the data that is in the flush cache, which is held in separate area of memory until it is committed to the index.
* All metadata for each shard is now stored in a single key with compressed value
* Creation of new metadata no longer requires a syncrhnous write to Bolt. It is passed to the WAL and written to Bolt periodically outside the write path
* Added DeleteSeries to WAL and updated bz1 to remove series there when DeleteSeries or DropMeasurement are called
Paul Dix
Ben Johnson