Path: utzoo!attcan!uunet!husc6!think!ames!umd5!uvaarpa!mcnc!rti!sas!cole
From: cole@sas.UUCP (Tom Cole)
Newsgroups: comp.os.vms
Subject: Re: Relinking/Recompiling for VMS 5.0
Summary: big application didn't need a relink
Keywords: VMS 5.0
Message-ID: <556@sas.UUCP>
Date: 20 Jun 88 12:00:35 GMT
References: <65@860800.UUCP>
Organization: SAS Institute Inc.,Cary NC,25712
Lines: 43

In article <65@860800.UUCP>, case@860800.UUCP (Bill Case) writes:
> Has anyone found  any reasons to relink or recompile
> ordinary application programs under VMS 5.0?  I have the 5.0
> Release Notes and New Features manuals which documents
> potential problems with writable global sections,  but I
> was wondering if there are any advantages to going to
> effort of relinking and (gasp!) recompiling.  It seems
> like you'd be running a bigger risk of making your VMS 5.0
> images unusable on VMS 4.x systems.
> 
> Bill "Born to be Mild" Case

Well, we happen to develop a large (read "monolithic") application,
consisting of almost 5 million lines of code.  It is contained in
about 300 separate images, which we dynamically load into memory
using the unsupported and ill-documented SYS$IMGACT service.  We
even unload the parts we are done with during execution.  Anyway,
the point is that we have a really big software package that even
does a few non-standard things.

We are able to run a version of this that was linked under VMS 4.2
on a VMS 5.0 system with no relink or other change, and it passes
our initial validation suites.

Digital (who has it now) tells us that we might gain a small
performance improvement by relinking, but of course then the
stuff wouldn't work in pre-5.0 systems.

But other than the minor and nebulous performance increase (in the
area of initial page faulting, I believe) the sucker seems to work
fine with no change.

The point is, I really believe them (this time) when they say that
you don't need to do anything special/wierd to use 5.0...


Tom Cole
SAS Institute
{anywhere}mcnc|rti|sas|cole

These opinions are *definitely* mine and not the official position
of SAS Institute (yet).  As soon as they agree with me, I'll let  
you know.