Re: Performance tuning

[Joe Pluta <joepluta@xxxxxxxxxxxxxxxxx>]

Yes indeed, the art vs. science aspect is exactly why I reached out to 
the community.  There are parts of the IBM i development environment 
where I consider my competent, and others where I don't, and tuning is 
definitely one of those areas where I'm not as certain.
Application review is definitely an ongoing issue.  We have a number of 
areas where we already know we're going to have to do some work.  But 
it's best to have a plan when going to the CIO - something a little more 
concrete than "we're going to have to fix everything".  :)

On 11/30/2018 4:22 PM, Jim Oberholtzer wrote:
> Until it's not.......
>
> If you have heavy SQL, them that setting can, not always certainly, and usually does, bollox things up.   It forces the optimizer to run for every query.  Sometimes it'll do a table scan, other times it'll build an index.  It may or may not use existing index objects.
>
> Mean time you're sitting there trying to understand why things run differently every day.
>
> Bottom line is, performance is as much art as science, and a solid understanding of the application is a good starting point.
>
> Jim Oberholtzer
> Agile Technology Architects
>
>
>
> > On Nov 30, 2018, at 12:19 PM, Roger Harman <roger.harman@xxxxxxxxxxx> wrote:
> >
> > When I had that responsibility, I just set QPFRADJ to '3' and was a happy camper.  Figured the machine was smart enough.
> >
> > Roger Harman
> > COMMON Certified Application Developer - ILE RPG on IBM i on Power