Hi,
There is a performance issue with the labelling service. Using labels makes even simple queries time out. For example this one:
SELECT $p $pLabel WHERE { $p wdt:P31 _:bnode . SERVICE wikibase:label { bd:serviceParam wikibase:language "en" . } } LIMIT 11
The workaround is to use subqueries. For example, the following query returns immediately:
SELECT $p $pLabel WHERE { { SELECT $p WHERE { $p wdt:P31 _:bnode . } LIMIT 11 } SERVICE wikibase:label { bd:serviceParam wikibase:language "en" . } }
I strongly suppose that almost every use of the labelling service could be performed like this (the only exception is when you apply further query conditions on the label). BlazeGraph should recognize this.
Meanwhile, everybody who uses queries with labels in an application should rewrite them as above to get the best performance (and reduce load on the query service ;-).
Cheers,
Markus