The DSL query 'mytype where property.id = "id1"' appears to be rewritten as a gremlin query that resembles:
g.V.has(typename, 'mytype'¨).as.out('property').has('id', 'id1').back('x')
On our system this query takes 6-7 minutes. The query
g.V.has('id', 'id1').in('property').has('typename', 'mytype')
takes 350 milliseconds.
g.V.count() = 1359151
We have atlas 0.7 installed. I've compiled the latest 0.9 code and looked at the generated gremlin query as reported in the logs for the same DSL-query, and I think 0.9 has the same performance issues. Unfortunately I don't have a big graph on a 0.9 installation to test performance.