Our current implementation has all calls to Neo4j through REST API. We are in process of replacing some of the code through neo4j-java-driver. We had some issues with performance which we tried to resolve through Cypher optimization and moving load from Neo4j DB to application layer. Using java driver, will it further reduce load on Neo4j DB or will just help in terms of reducing network latency?
The driver is a bit more optimal for some things. Version 1.5 will also allow async operations. The next major version will also provide backpressure and reactive operations.
It doesn't have to generate JSON anymore but will stream a binary protocol. So that might reduce the load a bit. I'm not sure, it will have a lot of impact.
Best to measure yourself.