RE: RPG IV Performance

["Richard Jackson" <richardjackson@xxxxxxxxxxxxxxxxxx>]

I suggest that we wonder why the rpg4 program is bigger.  I assert that the
code part of the rpg4 program is probably shorter than the code part for
rpg3 programs.  The rest of the object size is for debugging.  The rpg4
program could be smaller because the program optimizer is better - more
unnecessary instructions are eliminated during optimization.  If the rpg4
program isn't smaller, I suggest that it will be quicker - because the
optimizer is better.  In most cases, the size difference of the code will be
plus or minus up to 10 percent.  There will be exceptions where the code
size difference is larger than 10 percent.  Numbers like 10 percent do not
relate to the factor of 3 size difference reported by someone's consultant.
Reporting that a factor of 3 size difference is important reveals a
problem - the person reporting the difference doesn't understand the content
and/or functionality provided by the new program model.  We might wonder how
much they understand about rpg4.  We might also wonder if their advice on
this topic is valuable or if it should be followed.

Richard Jackson
(speaking only for myself)

-----Original Message-----
From: owner-rpg400-l@midrange.com [mailto:owner-rpg400-l@midrange.com]On
Behalf Of John Hall
Sent: Friday, January 19, 2001 10:22 AM
To: RPG400-L@midrange.com
Subject: Re: RPG IV Performance


Ditto to this.  Anybody who picks RPGIII over RPGIV because of program
size really doesn't understand performance issues.  Or more to the point
is still thinking in terms of a System 36 / RPGII.

I would bet that they tried it at some time in the past and had problems
with overrides and activation groups and reclaiming resources etc.  So
they use the size issue to discourage you from using something they had
trouble with.  But really is 500K extra memory (it won't be anywhere
near that much) going to matter on a machine with say 512 Mb memory?  Me
thinks not.

John Hall

jpcarr@TREDEGAR.COM wrote:
>
> Sounds like the "Consultant"   likes RPGIII and is not comfortable with
> RPGIV,  (ask him if the trigger program will use pointers to the before
and
> After image and not hard code the Before and After image area in the D/S.
> That will tell you if "He/She don't know RPGIV")
>
> I have about 60 triggers running on 8 AS/400's keeping our remote sites
> "Insync" with the central site.    No performance problems.
>
> If the Consultant worry's about Performance and object size FIRST and
> Functionality, Ease of Maintenance, and Bulletproofness,    I'd get
another
> consultant.
>
> Who the @#$ looks at the object size of a program to determine that you
> shouldn't write in RPGIV ?
>
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