Dear Kingsley,
thanks for your reply.
The overall triple counts of each instance is
- Virtuoso instance running at port 8891: 17765873 triples
- Virtuoso instance running at port 8893: 27897291 triples
- Virtuoso instance running at port 8895: 168888956 triples
- Virtuoso instance running at port 8899: 72372256 triples
If you are interested in the ini files, you can find the current versions at
https://www.dropbox.com/s/awdx744vomsb5vr/virtuoso_ini.zip?dl=0
For profiling I just used simple the test queries such that it is probably
easier to find out the problem. By doing so, I came to the assumption that
especially the size of the result set causes really long query evaluation time:
If I run q1:
SELECT ?x ?b
WHERE {
SERVICE <http://141.87.4.8:8891/sparql> {
?x <http://swrc.ontoware.org/ontology#edition> ?b .
} .
}
at lets say Virtuoso instance running at port 8895 it will end up within 2
minutes. This is because the service call will return only 32562 results.
But if I run q2:
SELECT ?x ?b
WHERE {
SERVICE <http://141.87.4.8:8891/sparql> {
?x <http://swrc.ontoware.org/ontology#pages> ?b .
} .
}
where the service call returns 313421 results, the query evaluation on the same
instance (running at port 8895) will take something around 1 hour!
The corresponding explain and profile plans of those queries can be found at
https://www.dropbox.com/s/ein0hxhtgk85ci9/analysis_files.zip?dl=0
Please notice that *_federated means the queries are like above and are
evaluated at the Virtuoso instance running at port 8895, and *_local means the
evaluation of these queries (without SERVICE) at the Virtuoso instance running
at port 8891.
On analyzing the long evaluation times, especially for q2 in the federated
case, I found out that if q2 is for example evaluated at Virtuoso instance
running at port 8895 and the Virtuoso instance running at port 8891 is shut
downed after 5 minutes, the query evaluation still proceeds and ended after
more than one hour with the same number of results (313421) as e.g. in the
local evaluation.
Please let me know if you need any other information.
Best regards
Andy
------------------------------------------------------------------------------
Site24x7 APM Insight: Get Deep Visibility into Application Performance
APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month
Monitor end-to-end web transactions and take corrective actions now
Troubleshoot faster and improve end-user experience. Signup Now!
http://pubads.g.doubleclick.net/gampad/clk?id=272487151&iu=/4140
_______________________________________________
Virtuoso-users mailing list
Virtuoso-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/virtuoso-users
