On Mon, Jun 25, 2012 at 1:34 AM, Frédéric Fondement <[email protected]> wrote: > My question was actually: given a table with millions, billions or whatever > number of rows, how fast is the TTL handling process ? How are rows scanned > during major compaction ? Are they all scanned in order to know whether they > should be removed from the filesystem (be it HDFS or whatever else) ? Or is > there any optimization making sure it can fatly finds those parts to be > deleted ?
All rows in the region(s) are processed during a major compaction. The process is a streaming merge sort of existing HFiles into a new HFile. Best regards, - Andy Problems worthy of attack prove their worth by hitting back. - Piet Hein (via Tom White)
