Neo4j is block based, it will only mark blocks as not in use but won't release them on disk. So your deletion of relationships won't make the database smaller on disk.
You're probably faster reimporting the data with the batch-inserter. Did you actually index the relationships? you have to batch your transactions around your delete operations and start a new Transaction every 50.000 elements. Otherwise you will run into GC issues which explain the slowness and GC overhead. Cheers, Michael ---- (michael)-[:SUPPORTS]->(YOU)-[:USE]->(Neo4j) Learn Online, Offline or Read a Book (in Deutsch) We're trading T-shirts for cool Graph Models Am 11.03.2014 um 11:23 schrieb Rita <[email protected]>: > Hi everybody > > I have populated my graph with nodes and relationships with the > BatchInserter. Now I need to delete a part of relationships, to reduce the > disk space of the graph. I have some problem. I am using the embedded version > of Neo4j with Java. > > I am using the instruction indexRel.remove(rel) to delete relationships from > the index, and it is ok. > > Instead I am using r.delete() inside transaction to delete them from the > graph. This is very slow, does exist another method instead of the > transactional one? I need also to close and reopen the graph to do not have > the error: GC overhead limit exeeded. Someone have a suggestion, please? > > Then, why after deleting relationships, the size of the graph on disk do not > decrease? > > Thank you very much in advance. > > Rita > > > -- > You received this message because you are subscribed to the Google Groups > "Neo4j" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Neo4j" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
