RE: Question about WebSphere & CMP

If you are new to WebSphere and J2EE, I would recommend to go "by the
numbers". 

Follow every standard practice, go with the mainstream, and after you have a
working app -no earlier- decide whether you have performance issues and
where. I've seen too many developers started creating their own convoluted
persistent mechanisms just because they read somewhere about EJBs
performance problems, for example. You could convert later a CMP bean into a
BMP if -a big IF- absolutely necessary.

In my own experience, no BMP + service program / java toolbox solution could
be noticeably more performant than the standard CMP mechanism, provided of
course that most recommendations and best practices were taken into account.
We have several banking apps running with iSeries WebSphere, no BMPs at all,
no JDBC performance complaints.

Hope this helps,


Sergio Carabetta
Software Engineer
Banco Itau Buen Ayre
Buenos Aires, Argentina



>> message: 2
>> date: Mon, 25 Oct 2004 10:20:31 -0400
>> from: Tom Daly <TDaly@xxxxxxxxxxxxxx>
>> subject: Question about WebSphere & CMP
>> 
>> 
>> How does Websphere handle container managed persistence?  
>> Does it use JDBC to 
>> interface with the database or does it go directly to the db 
>> via the same interfaces 
>> used by the HLLs?
>> 
>> I'm very curious about this because I have a sticking point 
>> about SQL related 
>> technologies for data-entry oriented apps.  (for reporting 
>> ok, for other than 
>> that...  but let's skip that discussion for now!)
>> 
>> If it does use JDBC then I'd be inclined to use BMP and get 
>> at the DB with either 
>> the javatoolbox or integrate with a service program or some 
>> such.  I have to tell 
>> you that currently I have no real experience with WebSphere, 
>> just "book knowledge", 
>> so any and all info, suggestions and insight is most 
>> welcome.  "Native" access to 
>> the db is a unique difference from other platforms that, for 
>> performance reasons, I 
>> think would be worth exploiting.
>> 
>> Oh - and before I forget to mention it, there's interesing reading at
>> http://publib.boulder.ibm.com/infocenter/wbihelp/index.jsp?to
>> pic=/com.ibm.wasee.doc
>> click on "Container Managed Persistence over Anything" in 
>> the "Server Foundation" 
>> chapter.   Makes me think that perhaps you could use CMP but 
>> have the performance of 
>> directly accessing the database.
>> 
>> 
>> Tom D.