private synchronized long getLevel0TargetTime() {
    long level0TargetTime = levelScheduledTime[0].get();
    double currentMultiplier = levelTimeMultiplier;

    for (int level = 0; level < LEVEL_THRESHOLD_SECONDS.length; level++) {
      currentMultiplier /= levelTimeMultiplier;
      long levelTime = levelScheduledTime[level].get();
      level0TargetTime = Math.max(level0TargetTime, (long) (levelTime / currentMultiplier));
    }

    return level0TargetTime;
  }
Get the expected scheduled time of LEVEL0 based on the maximum scheduled time of all levels
after normalization.

<p>For example, the levelTimeMultiplier is 2, which means the expected proportion of level0-1
is 2 : 1. However, the actual proportion of levelScheduledTime of level0 and level1 is 3 : 2,
in this situation the expected time of level0 will be Math.max(3, 2 * 2) = 4.

@return the expected scheduled time of LEVEL0
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/schedule/queue/multilevelqueue/MultilevelPriorityQueue.java