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From Ian Dickinson <>
Subject Re: Reasoners, Datasets, Models
Date Mon, 13 Dec 2010 16:32:14 GMT
On 13/12/10 16:16, Benson Margulies wrote:
> Meanwhile, is there any advantage of reading the ontology tuples
> themselves into memory instead of into TDB?
Yes, for sure, if you're using the inference engine. The reasoners make
many, many checks into the model of the form "is triple <t>
present/absent?". If that check goes to TDB, at best you're hitting the
cache but at worst you'll be doing a disk operation. For a small model,
if I understand it correctly, TDB will have everything cached. But for a
larger model, you will likely pay a performance** penalty.



Ian Dickinson                   Epimorphics Ltd, Bristol, UK
cell: +44-7786-850536              landline: +44-1275-399069
Epimorphics Ltd.  is a limited company registered in England
(no. 7016688). Registered address: Court Lodge, 105 High St,
              Portishead, Bristol BS20 6PT, UK

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