Yes, you're right, thanks. I haven't had my head in the CORBA spec much lately :). But you do agree that in the typical J2EE usage scenario one would want a multi-threaded Orb that supports thread policies, etc. such as Visibroker?
>From: Krishnan Subramanian <[EMAIL PROTECTED]> >Reply-To: Krishnan Subramanian <[EMAIL PROTECTED]> >To: [EMAIL PROTECTED] >Subject: Re: ORB >Date: Mon, 14 Jan 2002 12:35:54 +0100 > >John, > >Actually the CORBA specification does not mandate the use of >threads at all. It is very much possible for an ORB implementer >to write an implementation that is not multi-threaded. > >In reality most vendors do provide a threading model built >into the ORB. So John, you are very much right that the >(default) behavior is implementation specific. > >The thread-per-request model actually works quite well in >small-medium scale applications. (This model generally supports >10+ threads at the minimum per CPU). The advantages to >this are that no explicit configuration is required and >requests will be handled immediately (that is, no waiting >time in theory) taking full advantage of the hardware. > >But this model can be problematic in the case when there >are a large number of requests. Here, the server would >have to spawn an additional thread per request and at a >certain threshold, you would find that the overhead of >managing the large number of threads (switching, priorities, >memory management etc) will eventually lead the system >to thrash around and fail. That is, the system will probably >use all available resources (CPUs primarily) but not really >do anything useful. > >In such a case, using an event queue in front of the thread >pool can be a possible solution. Here, the queue fill ups >during periods of burst activity and requests are handled >during periods of inactivity. Such a solution leads to >trading off response time for (additional) throughput. Such >a queue based solution has to configured and tuned for each >(heterogeneous piece of) hardware it has to run on - since >hardware [, OS and VMs] dictate the most efficient size of >the queue/pool combination. > >Our product (the Borland Enterprise Server - our J2EE and >CORBA 2.4 compliant ORB) supports the above mentioned strategies >(configurable). > >-krish > > > > -----Original Message----- > > From: A mailing list for Enterprise JavaBeans development > > [mailto:[EMAIL PROTECTED]]On Behalf Of John Harby > > Sent: Sunday, January 13, 2002 10:41 PM > > To: [EMAIL PROTECTED] > > Subject: Re: ORB > > > > > > Actually a CORBA compliant POA should support thread policies > > according the OMG specification (cf. sec 11.2.8.1) > > > > > > >From: Johan Eltes <[EMAIL PROTECTED]> > > >Reply-To: [EMAIL PROTECTED] > > >To: [EMAIL PROTECTED] > > >Subject: Re: ORB > > >Date: Sun, 13 Jan 2002 22:23:11 +0100 > > > > > >The JavaIDL Orb creates one thread for each request. The behaviour is > > >implementation-specific. Other ORBs may implement other strategies, >like > > >thread pools or managed queues. > > > > > >/Johan > > > > > >-----Original Message----- > > >From: A mailing list for Enterprise JavaBeans development > > >[mailto:[EMAIL PROTECTED]]On Behalf Of Daniel Legziel > > >Sent: den 13 januari 2002 21:13 > > >To: [EMAIL PROTECTED] > > >Subject: ORB > > > > > >Hi guys, > > > > > >Can anyone tell me how the ORB in CORBA treats concurrent requests from > > >client(s) to server(s) and vice versa? Is there a queuing dynamic that > > >treats them in a FIFO manner? > > > > > >Any insight would be highly appreciated, > > >Daniel > > > > >=========================================================================== >To unsubscribe, send email to [EMAIL PROTECTED] and include in the body >of the message "signoff EJB-INTEREST". For general help, send email to >[EMAIL PROTECTED] and include in the body of the message "help". > _________________________________________________________________ Send and receive Hotmail on your mobile device: http://mobile.msn.com =========================================================================== To unsubscribe, send email to [EMAIL PROTECTED] and include in the body of the message "signoff EJB-INTEREST". For general help, send email to [EMAIL PROTECTED] and include in the body of the message "help".
