On 25/09/12 11:58, Igor Brussilowski wrote:
Hi all,I create an InfModel based on the Jena's builtin OWLMicroReasoner, which is extended by my own rules for evaluation of equality of resources based on their owl:hasKey properties like this one: # assuming eg:K is an owl:hasKey property from domain eg:D (?a a eg:D) (?b a eg:D) notEqual(?a ?b) (eg:K owl:equivalentProperty ?e1) (?a ?e1 ?o1) (?b ?e1 ?o1) -> (?a owl:sameAs ?b) as well the rules equality1, equality2 and equality3 taken from the ruleset owl-fb-mini.rules. This model is populated repeatedly by a list of triples (ca. 800): // print triples count for (;;) { graph.getBulkUpdateHandler().add(triples); // print duration of add in seconds // print graph size } Could you please explain the following output? Why takes the add function so much time? triples: 842 add: 0 s graph size: 1408 add: 10 s graph size: 1408 add: 11 s graph size: 1408 add: 10 s graph size: 1408 add: 10 s graph size: 1408 ...
Hard to tell but I suspect it is just performance limitations of the current forward chainer.
Because the rules are working at the triple level and your rule has two completely ungrounded triple patterns in it then it effectively creates a cross product of the entire data set with itself (i.e. about 0.7M Tuples) those then have to get joined with the other clauses.
It would be better if rule chainer treated unground triple patterns separately and had indexing of the tuples in the join nodes. Indeed there's lots that could be done to improve the performance of the rule engine if anyone had time and support to do so.
Dave
