Endpoint no response after 6 SPARQL queries

Virtuoso Universal Server
,
1

Hey,

TLDR: After sending (might have been 5 before i am not sure) 6 SPARQL queries to the local SPARQL endpoint the cmd isnt showing any output (not proceeding and without providing an error message)

Setup:

  • Ubuntu 18.04
  • virtuoso-opensource-7.2.5 build from source
  • default ini
  • I am new to the Linux environment so i might have made a very dumb mistake… so feel free to point something out that i might have missed out.

So i created a simple jar:

while(true){
create Sparql query with jena
send query to local endpoint
}

After 6 iterations the cmd just stops outputting results (cmd not frozen; no error message) . If i send the queries e.g. to dbpedia it works just fine.

Any idea what could cause this issue?

Thanks in advance

Marcel

2

Please provide a copy of your virtuoso.ini and virtuoso.log files for review.

What datasets are loaded into your local instance and what is the total triple count ( select count(*) where {?s ?p ?o}) ?

What are the queries being executed ie do they return a large result set, is it the same query being executed etc ?

If you can provide a command line compilable version of this simple jar we would attempt to recreate locally ?

At the point the program stops responding, can you make a Virtuoso isql connection to the database, and if so run the status() command and provide the output.

3

Thanks for the quick answer.

ini, log, jar(localhost, 10second timeout, 1sec delay between executions) and status output:
https://drive.google.com/open?id=1XJuNklJGvIVCosBTG00bBfqPNaiLM_Cz

At the moment there are just the default datasets loaded.

I already had a local dbpedia instance running and the same problem existed. I removed everything to make sure i didnt mess something up when setting it up.

total triple count at the moment:
5615

The query:
SELECT ?d WHERE {
?d ?s ?g.
}
LIMIT 1

4

I am unable to download the TestServer.jar file thus there a permissions issue on the file ?

Also, what is the command and connect options to pass to make a localhost:8890 connection to run the TestServer.jar to attempt recreation ?

5

I set the permissions now to public. It takes like 1 minute (google is scanning for viruses and gives a warning…)

There are no arguments, if that is your question? The “http://localhost:8890/sparql” endpoint is hardcoded.

I also added the java file to the google drive folder, if you want to build the jar yourself.

6

Hey,

issue resolved. I didnt close the queryexecution.

Sry for the hassle and again thanks for the quick response.