Re: mixed index - Reindex is very slow
janusgraph-dev is for discussion on internal implementation details of JanusGraph itself. Questions about using JanusGraph, installation, configuration, and integrations should be posted on janusgraph-users. First-time posts are moderated and may not be visible immediately.
Could you please repost your question on janusgraph-users, so that I can copy the answer below on the right list?
Did you try to use the mapreduce way of reindexing?