Major Description
If the config "dfs.cblock.block.buffer.flush.interval.seconds" is set to an extremely low value i.e 1 sec. Then multiple dirty logs files are generated during block buffer flush with the same timestamp signature.
This can be avoided by keeping a notion of flush id in BlockBuffer manager, which can be incremented in BlockBufferManager#triggerBlockBufferFlush.
When block is restarted, then the current flush id can easily be reconstructed by comparing the timestamp of all the dirty log files choosing the max flushid + 1 as the next flush id.