docs: public void startSnapshotWithTargets(Collection<SnapshotDataTarget> targets, long now)
      {
          // TRAIL [SnapSave:9] 5 [all SP] Start snapshot by putting task into the site queue.
          //Basically asserts that there are no tasks with null targets at this point
          //getTarget checks and crashes
          for (SnapshotTableTask t : m_snapshotTableTasks.values()) {
              t.getTarget();
          }
  
          ArrayList<SnapshotDataTarget> targetsToClose = Lists.newArrayList();
          for (final SnapshotDataTarget target : targets) {
              if (target.needsFinalClose()) {
                  targetsToClose.add(target);
              }
          }
          m_snapshotTargets = targetsToClose;
  
          // Queue the first snapshot task
          VoltDB.instance().schedulePriorityWork(
                  new Runnable() {
                      @Override
                      public void run()
                      {
                          m_siteTaskerQueue.offer(new SnapshotTask());
                      }
                  },
                  (m_quietUntil + (5 * m_snapshotPriority) - now),
                  0,
                  TimeUnit.MILLISECONDS);
          m_quietUntil += 5 * m_snapshotPriority;
      }