OK thanks, sure you are right, I see in detail, the disk space of the directory is increased for files: files nioneo_logical.log.vXXX Are they necessary? Can I delete them after closing the db? Thanks
Rita Il giorno venerdì 14 marzo 2014 09:28:01 UTC+1, Michael Hunger ha scritto: > > If you don't insert/update at all, the graph size should not increase. > > Remember to restart before you insert to reuse the existing blocks. > > Cheers, > > Michael > > ---- > (michael > <http://twitter.com/mesirii>)-[:SUPPORTS]->(*YOU*)-[:USE]->(Neo4j<http://neo4j.org> > ) > Learn Online <http://neo4j.org/learn/online_course>, > Offline<http://www.neo4j.org/events> or > Read a Book <http://graphdatabases.com> (in Deutsch<http://bit.ly/das-buch> > ) > We're trading T-shirts for cool Graph Models <http://bit.ly/graphgist> > > > > > > > > Am 14.03.2014 um 09:16 schrieb Rita <[email protected] <javascript:>>: > > OK thank you, I decreased a little bit the number. > Until now I'm deleting without new insertion, but the size of the graph is > increasing! Is it normal? Does it depend on the block marking? > > Many thanks, > Rita > > Il giorno martedì 11 marzo 2014 15:02:45 UTC+1, Michael Hunger ha scritto: >> >> No, no need to restart the db, the code should look like this: >> >> Transaction tx = db.beginTx(); >> int count=1; >> for (Relationship r : relationships) { >> relIndex.remove(r); >> r.delete(); >> if (count++ % 50000 == 0) { >> tx.success(); tx.finish(); >> tx = db.beginTx(); >> } >> } >> tx.success(); tx.finish(); >> >> It depends on your heap how many elements can be handled in a single tx. >> You can also lower that number to 25000 >> >> Cheers, >> >> Michael >> >> ---- >> (michael <http://twitter.com/mesirii>)-[:SUPPORTS]->(*YOU*)-[:USE]->( >> Neo4j <http://neo4j.org/>) >> Learn Online <http://neo4j.org/learn/online_course>, >> Offline<http://www.neo4j.org/events> or >> Read a Book <http://graphdatabases.com/> (in Deutsch<http://bit.ly/das-buch> >> ) >> We're trading T-shirts for cool Graph Models <http://bit.ly/graphgist> >> >> >> >> >> >> >> >> Am 11.03.2014 um 14:45 schrieb Rita <[email protected]>: >> >> Ok, so it will not increase the space with new insertion, I hope to see >> soon this after resolving with the delete, because also if I start a new >> Transaction every 50.000 elements I got the GC error. It seems that I need >> to close and reopen also the graph to avoid this one. Does it keep all in >> memory also after tx.finish? But in this way it is too slow. Any other way >> to increase speed? >> Thanks >> >> Rita >> >> Il giorno martedì 11 marzo 2014 12:58:52 UTC+1, Michael Hunger ha scritto: >>> >>> Existing node and relationship records that are freed will of course be >>> reused (but only after a restart). >>> >>> So if you have a sliding window and delete nodes, then restart your db >>> before inserting the new window and it will use the existing record blocks >>> on disk. >>> >>> Cheers, >>> >>> Michael >>> >>> ---- >>> (michael <http://twitter.com/mesirii>)-[:SUPPORTS]->(*YOU*)-[:USE]->( >>> Neo4j <http://neo4j.org/>) >>> Learn Online <http://neo4j.org/learn/online_course>, >>> Offline<http://www.neo4j.org/events> or >>> Read a Book <http://graphdatabases.com/> (in Deutsch<http://bit.ly/das-buch> >>> ) >>> We're trading T-shirts for cool Graph Models <http://bit.ly/graphgist> >>> >>> >>> >>> >>> >>> >>> >>> Am 11.03.2014 um 12:10 schrieb Rita <[email protected]>: >>> >>> Thank you for the reply. >>> Really cannot exist a way to reduce the disk space? I need it. So how >>> could I do? >>> I cannot reimport the data from the beginning because I have to populate >>> the graph like a sliding window, I need to remove the older data l and then >>> import newer ones. >>> Does exist some way to "optimize" the graph and index space after those >>> deletes? >>> Yes I have an index on relationships, so I'm deleting them both from the >>> index and the graph. >>> >>> Thanks. >>> >>> Rita >>> >>> >>> Il giorno martedì 11 marzo 2014 11:34:54 UTC+1, Michael Hunger ha >>> scritto: >>>> >>>> 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 <http://twitter.com/mesirii>)-[:SUPPORTS]->(*YOU*)-[:USE]->( >>>> Neo4j <http://neo4j.org/>) >>>> Learn Online <http://neo4j.org/learn/online_course>, >>>> Offline<http://www.neo4j.org/events> or >>>> Read a Book <http://graphdatabases.com/> (in >>>> Deutsch<http://bit.ly/das-buch> >>>> ) >>>> We're trading T-shirts for cool Graph Models <http://bit.ly/graphgist> >>>> >>>> >>>> >>>> >>>> >>>> >>>> >>>> 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. >>> >>> >>> >> -- >> 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] <javascript:>. > For more options, visit https://groups.google.com/d/optout. > > > -- You received this message because you are subscribed to the Google Groups "Neo4j" group. 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