Re: RPG IV Performance

["David Morris" <dmorris@xxxxxxxxxxxxx>]

Lisa,

Whether the program is written in RPGIII or RPGIV will have very little impact. 
 I would 
guess that program size only comes into play when you set on LR in the trigger, 
which 
you should avoid at all costs if performance is an issue. A trigger on a file 
will have a 
big impact on update and write performance to that particular file.  We have 
triggers on 
nearly all of our files and have found that a trigger that simply returns 
increases I/O time 
by a factor of 3-4.  This is only noticeable when you are firing a trigger for 
a large number 
of records during a transaction.

David Morris


>>> Lisa.Abney@universalflavors.com 01/19/01 06:06AM >>>


Hi all!  I've just heard some rather negative performance things on RPG IV, and
wonder if anyone can give me some feedback on how true this might be.

We're working with a consulting company who is doing some performance analysis
on some of our programs.  They seem very knowledgeable, and I have a lot of
confidence in what they've done up until now.  However, today they were showing
us a mock-up of a trigger program they want to use.  As they explained it, this
trigger program will be constantly running in the background for every user on
the system to monitor changes to two files, and will feed data to a dataque.
The program they showed me was written in RPGIII, and I made my usual request to
an outside contractor that this be done in RPGIV.  His response was "Sure, if
you want the program size to be 5 - 10 times the size of an RPGIII program."
When I asked him to explain that, he only said that, in his experience, this is
always true, and that it would have a very negative performance.  I even
mentioned removing observability (not that I really understand what that means,
but I just read something the other day about that being a way to reduce program
size!), and he said that might move it down to 3 - 5 times the size of an
equivalent RPGIII program.  The program will only be about 50 - 100 lines of
code.

Can someone explain if this is true, and, if so, why?  And, if true, what does
this really mean from a performance standpoint?

+---
| This is the RPG/400 Mailing List!
| To submit a new message, send your mail to RPG400-L@midrange.com.
| To subscribe to this list send email to RPG400-L-SUB@midrange.com.
| To unsubscribe from this list send email to RPG400-L-UNSUB@midrange.com.
| Questions should be directed to the list owner/operator: david@midrange.com
+---