It's possible that you're seeing a GC spike. Would you mind adding GC monitoring[1] to your output to see if that is related?
Best, Andreas [1] http://www.oracle.com/technetwork/java/gc-tuning-5-138395.html#0.0.0.Measurement%7Coutline On Nov 16, 2010, at 8:09 PM, Rick Bullotta wrote: > My first guess with that big a difference would be a bug in the > calculation/output of the benchmark timing! > > -----Original Message----- > From: user-boun...@lists.neo4j.org [mailto:user-boun...@lists.neo4j.org] On > Behalf Of Martin Grimmer > Sent: Tuesday, November 16, 2010 4:47 AM > To: user@lists.neo4j.org > Subject: [SPAM] [Neo4j] strange performance > > Hello, > > currently we evaluate Neo4j for one of our projects. > Our tests showed some strange behaviour to us: > > ... > at query 941/10000000 (0,009410) with 1809 mb in 0,300000 seconds - > avg: 0,308696 - max: 54,533000 > at query 942/10000000 (0,009420) with 1809 mb in 0,069000 seconds - > avg: 0,308441 - max: 54,533000 > at query 943/10000000 (0,009430) with 1809 mb in 0,057000 seconds - > avg: 0,308174 - max: 54,533000 > at query 944/10000000 (0,009440) with 1809 mb in 0,038000 seconds - > avg: 0,307888 - max: 54,533000 > at query 945/10000000 (0,009450) with 1809 mb in 0,630000 seconds - > avg: 0,308229 - max: 54,533000 > at query 946/10000000 (0,009460) with 1809 mb in* 60,997000 seconds* > - avg: 0,372450 - max: 60,997000 > ... fast again > > Our Neo4j database is about 9 GB in size with about 130M arcs and 15M > nodes. > A query gets two strings as input, these are keys for the lucene index > service to get access to two nodes. Then we start > an algorithm for these two nodes which determines nodes which are > adjacent (by 2 steps BFS) to both restricted to only one specific arc type. > I dont know why some queries are so much (> x100) slower. Maybe you are > able to help me? > > best regards > -- > > * Martin Grimmer * > Developer, Semantic Web Project, IT > > Unister GmbH > Barfußgässchen 11 | 04109 Leipzig > > Telefon: +49 (0)341 49288 5064 > martin.grim...@unister.de <mailto:%0a%20%20martin.grim...@unister.de> > www.unister.de <http://www.unister.de> > > Vertretungsberechtigter Geschäftsführer: Thomas Wagner > Amtsgericht Leipzig, HRB: 19056 > > _______________________________________________ > Neo4j mailing list > User@lists.neo4j.org > https://lists.neo4j.org/mailman/listinfo/user > > _______________________________________________ > Neo4j mailing list > User@lists.neo4j.org > https://lists.neo4j.org/mailman/listinfo/user _______________________________________________ Neo4j mailing list User@lists.neo4j.org https://lists.neo4j.org/mailman/listinfo/user
