Thanks a lot for your reply! As you have assumed, I don't use neither TDB or SDB...I have an in memory- model at runtime. It seems to me that my model does not require complicate inferences...at every step, it extracts a tuple from the DB and generates the corresponding individuals with: model.createIndividual; the properties are added using the addProperty method.
The only thing that can be complicated to be calculated is that, if an individual has the same id of the last one processed, I extract the latter from the ontology to add some properties... thanks a lot again! Paola >----Messaggio originale---- >Da: [email protected] >Data: 30/03/2012 13.56 >A: "[email protected]"<[email protected]> >Cc: <[email protected]> >Ogg: Re: Re: Jena slow ontology population > >your hardware looks good, what type of inference does your model >require for updates? > >Pellet is a very powerful reasoning system which can result in >significant computational complexity for the subsystem to deal with >depending on your level of inference that is of course. So you better >know exactly what level of reasoning your application requires in >advance to optimize the system at run-time. > >TBD, SDB are persistent storage options, from what you have just said >I can assume you are using an in-memory model at run-time. > > > > >On Fri, Mar 30, 2012 at 7:41 AM, [email protected] <[email protected]> wrote: >> Hi Marco, thanks a lot for your help! :-) >> >> Version of Jena: 2.6.4 >> OS: Linux 64 bit >> reasoner: Pellet >> TDB and SDB: I don't use them, I believed that they were related to RDF while >> I'm using OWL, but maybe I can be wrong... >> >> current hw: >> *-CPU >> description: CPU >> product: Intel(R) Xeon(R) CPU >> version: Intel(R) Xeon(R) CPU E5620 >> slot: CPU 1 >> size: 2400MHz >> capacity: 2400MHz >> width: 64 bits >> clock: 133MHz >> *-memory >> description: System Memory >> physical id: 24 >> slot: System board or motherboard >> size: 8GiB >> >> If you want to know other information, please tell me! And thanks a lot again! >> >> Paola >> >>>----Messaggio originale---- >>>Da: [email protected] >>>Data: 30/03/2012 11.36 >>>A: <[email protected]>, "[email protected]"<villa.va@libero. >> it> >>>Ogg: Re: Jena slow ontology population >>> >>>can you please be a bit more specific about the configuration you have >>>currently installed? e.g. version of Jena, back end type (TDB, SDB, >>>in-memory), current hardware, and OS (32bit, 64bit, linux, >>>windows,mac), and type of reasoner you use. >>> >>>--- >>>Marco Neumann >>>KONA >>> >>>Join us at SemTech Biz in San Francisco June 3-7 2012 and save 15% >>>with the lotico community discount code 'STMN' >>>http://www.lotico.com/evt/SemTechSF2012/ >>> >>>On Fri, Mar 30, 2012 at 4:22 AM, [email protected] <[email protected]> >> wrote: >>>> Dear users, >>>> >>>> I am new to Jena and have a problem with Jena OWL-API. I have written some >>>> simple Java code that: >>>> >>>> 1) extracts some tuples (around 1 million tuples) of data from a database >>>> 2) puts each of them in an ontology file using Jena library. In particular, >> it >>>> takes every tuple and inserts >>>> every element in a class of the ontology file, by using methods like >>>> createIndividual, addproperty, model.write. >>>> >>>> The insertion phase is very quick when my program starts, but the >> performances >>>> became worse and worse as >>>> time goes by. The DB man has told me that the database has no problems. I >> have >>>> run the program with 5 gigabytes >>>> of RAM...it simply ends up to use them all. Is that normal? Do I have to >> use a >>>> more powerful PC to manage such >>>> data? I can give you more details about my problem if you tell me what I >> have >>>> to look for exactly. >>>> >>>> Thanks a lot, >>>> >>>> Paola >>> >> >> > > > >-- > > >--- >Marco Neumann >KONA > >Join us at SemTech Biz in San Francisco June 3-7 2012 and save 15% >with the lotico community discount code 'STMN' >http://www.lotico.com/evt/SemTechSF2012/ >
