问题
Suppose we have an edge or a vertex but we don't need that vertex anymore when we delete that vertex does orientdb use that space again that was allocated to the deleted vertex or edge.
回答1:
The space is reused, but the RID (Record ID) is never recycled.
来源：https://stackoverflow.com/questions/26160635/do-orientdb-use-the-deleted-vertex-or-edge-memory