code: void clearReplicationQueues() {
      writeLock();
      try {
        synchronized (neededReplications) {
          neededReplications.clear();
        }
        underReplicatedBlocksCount = 0;
  
        corruptReplicas.clear();
        corruptReplicaBlocksCount = 0;
  
        overReplicatedBlocks.clear();
        raidEncodingTasks.clear();
  
        excessReplicateMap = new HashMap<String, LightWeightHashSet<Block>>();
        excessBlocksCount = 0;
      } finally {
        writeUnlock();
      }
    }
docs: Clear replication queues. This is used by standby avatar to reclaim memory.