Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!gatech!ukma!xanth!ginosko!uunet!cs.utexas.edu!milano!cadillac!joy!speyer From: speyer@joy.cad.mcc.com (Bruce Speyer) Newsgroups: comp.databases Subject: Re: Extended RDB vs OODB Message-ID: <2230@cadillac.CAD.MCC.COM> Date: 14 Aug 89 15:51:47 GMT References: <3560052@wdl1.UUCP> <411@odi.ODI.COM> <458@cimshop.UUCP> <2177@cadillac.CAD.MCC.COM> <20@dgis.daitc.mil> Sender: news@cadillac.CAD.MCC.COM Reply-To: speyer%cad@MCC.COM (Bruce Speyer) Organization: MCC CAD Program, Austin, TX Lines: 33 In article <20@dgis.daitc.mil> jkrueger@dgis.daitc.mil (Jonathan Krueger) writes: >speyer@joy.cad.mcc.com (Bruce Speyer) writes: > >>If an application must cross its process boundary in order to >>communicate with the database system it probably is at least two orders >>of magnitude too slow. That is why all of the C++ based OODBMS efforts >>are using the application memory heap for the cache. > >Could you provide some performance measurement data that qualify >and quantify this assertion? > >-- Jon No, I don't have the numbers or the time to work them up. Perhaps somebody else could provide actual statistics and even disprove my assertion. It would be interesting to hear from somebody involved with the HP Iris system which is based upon a relational database. About 3 years ago I tried putting an electronic information model on top of a relational system. It took about 30-40 times longer to netlist a circuit then it did using a fairly inefficient internally developed memory-based database system. An operation such as packaging the electronics is much worse since it must transverse much more of the electronic information model and be constantly refering to the library portion of the model which was distributed to another database (making the join operation much more expensive). Compare the cost of processing a tuple at a time to a C++ style database. If the object is in-memory then optimally an indirect reference and a test is all that is required to transverse a relation or access an attribute. My apologies for not being able to back up my statements with benchmarks. Bruce Speyer / MCC CAD Program WORK: [512] 338-3668 3500 W. Balcones Center Dr., Austin, TX. 78759 ARPA: speyer@mcc.com