docs: public void mergeTracker(DRConsumerDrIdTracker tracker) {
          final long newSafePoint = Math.max(tracker.getSafePointDrId(), getSafePointDrId());
          m_map.addAll(tracker.m_map);
          truncate(newSafePoint);
          m_lastSpUniqueId = Math.max(m_lastSpUniqueId, tracker.m_lastSpUniqueId);
          m_lastMpUniqueId = Math.max(m_lastMpUniqueId, tracker.m_lastMpUniqueId);
      }