[OAK-3479] Add generation info to compaction map

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 1.3.8, 1.4
• Component/s: segmentmk
• Labels: cleanup compaction gc
• Epic Link: SegmentMK revision GC
• Assignee: Alex Deparvu
• Reporter: Alex Deparvu
• Created: 06/Oct/15 08:37
• Updated: 02/Mar/16 14:31
• Resolved: 06/Oct/15 10:12

Description

I'd like to add a counter that exposes the current generation of the compaction map, (meaning the number of compaction cycles).
So far I've been using the CompactionMap#getDepth as a heuristic but if you run long enough some old generations will be dropped decreasing the depth, making it unreliable as a generation counter.
I don't want to persist this info, just start at 0 once the system starts up and increase on each CompactionMap#cons call.