@Override
  public long ramBytesUsed() {
    return INSTANCE_SIZE
        + MemoryEstimationHelper.getEstimatedSizeOfAccountableObject(operatorContext)
        + MemoryEstimationHelper.getEstimatedSizeOfAccountableObject(child)
        + RamUsageEstimator.sizeOf(databaseName)
        + MemoryEstimationHelper.getEstimatedSizeOfPartialPath(devicePath)
        + MemoryEstimationHelper.getEstimatedSizeOfPartialPath(seriesPath)
        + tsBlockBuilder.getRetainedSizeInBytes();
  }
update last cache for aligned series.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/operator/process/last/AlignedUpdateLastCacheOperator.java