We have a social graph in which in a day we add almost 1 millions of node and twice as many edges. We started with neo4j graph because yes, it is very fast due to fact that its storage is on the same machine on which graph engine runs. But following are the experiences that we would like to share with you about neo4j.
- Not good fit for real time query. We have social structure like twitter. We have to show latest 20 activities (and its associated activities) of all the users that a user follow on his time line.
We have some users who follows more than 1000 users. The gremlin query that we wrote for this (if you are interested then we can share gremlin query) really produced so much GC that a server with 8 cpu and 48 gb ram used to freeze and we had to restart the server to get it online again. - Many a time network partition observed.
- There is not vertex centric index that is very much required in graoh database.
Ultimately we are so much fade up with server performance with gremlin query that we had to change the database to titan.
On titan we are getting reasonable performance and also scaling is very easy as we are using cassandra as backend storage. But mind you that .. using gremlin here also not a good idea as multiget query is very ugly to write and without multiget its query becomes very slow.