@Override
  public IMNodeIterator<IConfigMNode> getTraverserIterator(
      IConfigMNode parent, Map<Integer, Template> templateMap, boolean skipPreDeletedSchema)
      throws MetadataException {
    if (parent.isDevice()) {
      AbstractTraverserIterator<IConfigMNode> iterator =
          new MemoryTraverserIterator<>(this, parent.getAsDeviceMNode(), templateMap, nodeFactory);
      iterator.setSkipPreDeletedSchema(skipPreDeletedSchema);
      return iterator;
    } else {
      return getChildrenIterator(parent);
    }
  }
This is a memory-based implementation of IMTreeStore. All MNodes are stored in memory.
iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/persistence/schema/ConfigMTreeStore.java