2016-04-01 Virtuoso, Rya and where we go from here
Time:Ā 9:00am PDT / Noon EDT
WebEx Info:Ā Join WebEx meeting - Meeting # 649 933 963 , Meeting password:Ā htIG0401Ā (hotel-tango-Igloo-Golf-zero-three-zero-oneĀ I'm not sure you need the password.)
Audio Connection:Ā Computer, or 1-855-244-8681 Call-in toll-free number (US/Canada), or 1-650-479-3207 Call-in toll number (US/Canada)
Moderator: E. Lynette Rayle (Cornell)
Notetaker:Ā tamsin woo
Attendees:
Agenda:
- Next Call
- date/time: 2016-05-20Ā
- Moderator:Ā
- Notetaker:Ā
- Call for additional agenda items
- Status of Triplestore Implementations in Ruby
- Aaron Coburn - Rya (Apache project)
- Triplestore via Apache runs on top of Hadoop/Accumulo
- Highly scalable
- SPARQL queries are mapped into Pig for MapReduce
- This is a fairly new project; and is a lot of work to set-up, largely due to Hadoop
- Q: Were you able to load data in?
- Just barely got it running. Can attest to the fact that it is hard to setup.
- Q: Do we have a sense of scale & performance?
- Not really; guessing: simple queries are probably more costly, but complex queries are where you might see the benefits.
- Q: How much is kept in memory?
- Don't really know, would need to look into Accumulo.
- Q: SPARQL Update support?
- Yes. In principle, the existing Ruby SPARQL::Client::Repository should work.
- RYA Paper:Ā http://sqrrl.com/media/Rya_CloudI20121.pdf
- Corey Harper - Virtuoso
- Jim Blake joins to talk about LD4L Virtuoso scalability
- Working with around 1 Billion triples
- Dealing with crashing on many subsequent SPARQL Queries
- The work-around is to run 1.5 million queries then restart Virtuoso
- The queries look like all properties from a named node and rdf:type statements from them.
- Using latest stable release (probably version 7?)
- Notes Document:Ā http://bit.ly/virtuoso-hydra
- Corey had done some work on OpenRefine, discovered that the DERI LinkedData plugin
- The UI is called Virtuoso Conductor
- The RDF.rb support is community supported and is over 2 years old; doesn't work with RDF.rb 1.1.x+
- Virtuoso Index Scheme documentation:Ā
- Jim Blake joins to talk about LD4L Virtuoso scalability
- Aaron Coburn - Rya (Apache project)
- Where Next - Direction of the Group
- Goals
- Can we push toward LDP as a common gateway?
- Have the application talk to a triplestore directly, with eventual persistence to Fedora
- Look at Fedora API work; which Fedora functions map to a triplestore backend.
- See:Ā https://github.com/fcrepo4-labs/derby
- Derby talk next meeting.
- General Graph Database discussion?
- Has anyone used Neo4J?
- Hector is willing to do a Neo4J overview next meeting.
- Has anyone used Neo4J?
- Goals