Concurrent DU Detection Issue
- DU2 is concurrent DU, but:
- DU2 is handled quicker than the DU1 by middle layer;
- DU2 is removed from both PPU set and UMQ before VM gets the query result QR.
- VM can no longer detect concurrent DU2.
- Use RPU stores all related Processed Updates
- Related concurrent DU: There exists at least one DU received earlier, which hasn’t been completely handled by the view maintenance module yet.