OWLIM is a high-performance semantic repository developed in Java. It is packaged as a Storage and Inference Layer (SAIL) for the Sesame RDF framework. OWLIM is based on TRREE – a native RDF database and rule-entailment engine.

The semantics, supported by OWLIM, can be configured through rule-set definition and selection. The most expressive pre-defined rule-set combines unconstrained RDFS with most of OWL Lite (as indicated on the OWL fragments map).

OWLIM is available in several versions, tailored to meet different requirements as discussed in the version map. The two major flavors of OWLIM are:

• SwiftOWLIM, performing reasoning and query evaluation in-memory, while a reliable persistence strategy assures data preservation and consistency. It scales to about 10 mill. statements on a 32-bit notebook and further, when proportional amount of memory is allocated.
• BigOWLIM, operating with file-based indices, which allows it to scale to billions of statements even on desktop machines.

SwiftOWLIM is the fastest RDF(S) and OWL engine! It can load and materialize LUBM(50) within 42 sec. on desktop machine, delivering unmatched throughput of 161 KSt./sec.

BigOWLIM is the most scalable inference engine, capable to perform reasoning against 12 billion triples! It is also the only engine proven to support non-trivial OWL inference with more than 1 billion statements of real-world data: check the 1.5 billion statements of LinkedLifeData.

BigOWLIM is the most scalable and efficient RDF Database! It was proven to deal with 20 billion triples on a $10 000 worth server. It can manage 1 billion statements on $2000-worth desktop, delivering the best published "full cycle" results for LUBM(8000).

Performance evaluation results and analysis can be found here.

SwiftOWLIM v2.9.1: http://www.ontotext.com/owlim/v2.9.1/owlim-2.9.1.zip

SwiftOWLIM v3.0.10: http://www.ontotext.com/owlim/swiftowlim-3.0.beta10-sesame-2.0.zip

Earlier versions are available here. Release notes are available in the change log.

Documentation: Presentation, SwiftOWLIM's Fact Sheet and SwiftOWLIM System Documentation.

Mailing lists subscription available on OWLIM Mailing lists.

SwiftOWLIM is an open-source library, under LGPL. Please, read SwiftOWLIM's Licence Agreement.

BigOWLIM is available under an RDBMS-like commercial licence on a per-server-CPU basis; it is neither free nor open-source. To purchase a licence or obtain a free copy for research or evaluation, please, contact OWLIM-info-at-ontotext.com.

OpenRDF is an open source project of Aduna, supporting and developing Sesame. The latter is ranked by multiple indepedent evaluations as the most efficient RDF repository framework. OWLIM uses Sesame as a library, taking advantage of its APIs for storage and querying, as well as the support for a wide variety of query languages (e.g. SPARQL and SeRQL) and RDF syntaxes (e.g. RDF/XML, N3, Turtle).

The development of OWLIM is partly supported by SEKT, TAO, TripCom, LarKC, and other FP6 and FP7 European research projects.