Re: Performance issues with ILE

[Peter Levy <plevy@xxxxxxxxxxxx>]

ali.juzer@xxxxxxxxx wrote:
> Hi All,
>
>
>
> As part of our enhancement project, we changed many of our AS/400 OPM
> programs to ILE. We compiled the programs with ACTGRP = *CALLER unless
> in cases where some specific programs required other activation groups.
>
>
>
> After the successful conversion, we are now having performance issues.
> The batch programs, which were previously in OPM COBOL, but now in ILE
> COBOL, are taking huge time - almost 1.5 to 2 times.  Please let me know
> if someone has undertaken such projects or solved such issues.
>
>
>
> Note: We didn't recode our programs. We use SYNON/2E for code
> generation; we changed only the target type (OPM to ILE) and recompiled
> our programs.
>
>
>
> Thanks
>
>
>
> Ali Asgar
>
> Wipro Technologies
>
> Ph +91 20 22933700  3343
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There are several things that I would do:

1) Convert all of your ILE programs to run in the QILE activation group. 
Currently you've got a bunch of Synon/2E OPM programs, which all run in 
the *DEFAULT activation group, so specifying *CALLER means they'll only 
run there. Specifying *NEW can a performance hog and should only be used 
when you have a specific reason. Mixing *NEW and *CALLER can work but 
it's complicated to maintain. Having everything in one ILE activation 
group is the simplest to run and maintain.

2) Optimize your programs to *FULL. This will give you access to the 
"instruction piping" feature of ILE which will improve performance. You 
might also want to study the advanced optimization techniques in the ILE 
Concepts manual: 
http://publib.boulder.ibm.com/infocenter/iseries/v5r4/topic/books/sc415606.pdf

3) If your data is at one CCSID and your jobs are at another there is 
going to be a lot of data conversions going on. You might want to look 
at that as a possible culprit.