heapspace problem with Jena (OntModel) and TDB

[Ingo Roderfeld]

Hi,

I'm trying to search in (and manipulate) a large ontology that is stored 
in a TDB. At first I'm fetching the Jena model from the TDB with the command

Model tdbModel = TDBFactory.createModel("/some/path/to/NCI-Thesaurus");

I than want to convert it into an OntModel, because of the convenience 
functions this model offers:

OntModel ontModel = ModelFactory.createOntologyModel(
        OntModelSpec.OWL_DL_MEM_RDFS_INF, tdbModel);

After this I'm trying to obtain a special class and a special property 
of the model:

OntClass ontClass = ontModel.getOntClass(
"http://some/uri/Thesaurus.owl#C16612";);
OntProperty op = ontModel.getOntProperty(
"http://some/uri/Thesaurus.owl#P108";);

After some minutes the program aborts with an OutOfMemoryError, although 
I've allocated 2G heapspace to the program.

Thanks in advance for any hints.

Ingo Roderfeld