Path: csiph.com!au2pb.net!feeder.erje.net!1.eu.feeder.erje.net!newsfeed.fsmpi.rwth-aachen.de!newsfeed.straub-nv.de!eternal-september.org!feeder.eternal-september.org!mx02.eternal-september.org!.POSTED!not-for-mail From: Cecil Westerhof Newsgroups: comp.lang.java.programmer Subject: Performance JPA Date: Fri, 20 Nov 2015 09:41:56 +0100 Organization: Decebal Computing Lines: 21 Message-ID: <87h9khysdn.fsf@Equus.decebal.nl> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: mx02.eternal-september.org; posting-host="528adfd6ad074c92fdc6a7f8fb9e23d8"; logging-data="15951"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+ry22hDUxg5qzdThEmCp2mta3MNhZ9moY=" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) X-Homepage: http://www.decebal.nl/ Cancel-Lock: sha1:nJ4EqFqyHlrxBar2ppo1G8ulHOM= sha1:tW02QD5TA14jE38gBcABbYTrAOs= Xref: csiph.com comp.lang.java.programmer:33151 I am at the end of my first JPA project. At the moment we are working with one entity manager in the application. I heard that it could be a good idea to use several entity managers, because that could improve the performance. Is this true, or just a myth? Also I was told that Hibernate is about three times as fast as openJPA. We are required to use openJPA because we are using the IBM Web Application Server. The performance with openJPA is about the same as when the application used JDBC. So then it looks not very reasonable to think that Hibernate will be three times as fast as openJPA. But I also understood that IBM WAS uses a highly optimised version of openJPA. Is it true that Hibernate is a lot faster, or is it a case of: lies, damned lies and statistics? -- Cecil Westerhof Senior Software Engineer LinkedIn: http://www.linkedin.com/in/cecilwesterhof