Re: frequent manipulation of jobs library list

["Mark Murphy/STAR BASE Consulting Inc." <mmurphy@xxxxxxxxxxxxxxx>]

I have a process that can do something similar.  Processing messages from a queue.  A table tells what to do with it, and how to process it, including whether the library list needs to be changed or not.  This worked great on low volume queues, but it turns out that changing the library list isn't a cheap operation.  As the volume picked up, the jobs couldn't keep up until we told all the jobs to use the same library list.

Mark Murphy
STAR BASE Consulting, Inc.
mmurphy@xxxxxxxxxxxxxxx

-----midrange-l-bounces@xxxxxxxxxxxx wrote: -----

To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxx>
From: Charles Wilt <charles.wilt@xxxxxxxxx>
Sent by: midrange-l-bounces@xxxxxxxxxxxx
Date: 12/23/2009 01:08PM
Subject: Re: frequent manipulation of jobs library list

Joe,

This might not even work.  RPG normally resolves a pointer to a
program only once.  Which means if you change the library list between
calls, it doesn't affect the program being called.

In other words, say you've got a PGMA that looks like so:
/free
  dow not done;
     CallPgmToSetLibl();
     // do some work
     callp PGMB();
     // more work
     GetNextTransaction();
  enddo;
/end-free

The PGMB found during the first loop will be the one called for all
subsequent loops, even if the library list has changed and a beta
version of PGMB is now ahead of the original in the library list.

You can find more discussions about this in the archive.


HTH,
Charles

On Wed, Dec 23, 2009 at 11:55 AM,  <joe.goray@xxxxxxxxx> wrote:
> Is there any impact or considerations related to constantly changing a
> jobs library list, either by adding/removing a library or by changing the
> curlib?
>
> We are trying to develop a methodology for providing a "beta" environment
> based on a facility number.  One idea is to create a set of beta libraries
> where beta code will be installed.  Based on a control file that would
> contain facilities included in the beta.  If they are a beta facility, the
> beta library would be added to the top of the libl (or made the curlib).
> If it's not a beta facility, the beta library will be removed from the
> libl.
>
> Our processes don't process data by facility, so this approach would
> likely be changing the libl every transaction, which is high volume.  Some
> of these processes run 24X7.
>
> Would manipulating the library list this frequently impact job performance
> and/or system performance?
>
> Thanks
> Joe
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