Re: Optimizing File I-O in RPG IV/ I-Series

Hi Jim, the first is just a question, no triggers on the file to update?
Sometimes bad coded triggers are performance killers.

Second you can try to code:

setll key file;
if %equal;
  dow 1 = 1;
    reade key format;
    if %eof;
      leave;
    endif;
    ...
  enddo;
endif;


Last, if you are not updating all or most of the fields try to use:

update format  %fileds(field1:field2....);

HTH
Marco
--- Jim Wiant <Jim.Wiant@xxxxxxxxxxxxxxxx> wrote:

> We have a series of programs that update files for assorted maintenance.
> The time these programs are taking is becoming excessive.
> 
> In most cases, the RPG code is very simple.
> 
> Key   SETLL                   file
> Key   READE                   file
>       (Do until EOF)
>       UPDATE          record
> Key   READE                   file
>       END DO
> 
> I don't see how the code can get might tighter. Is there any reasonable
> compiling options/ CL overrides, etc. that could improve such a routine
> when it
> needs to process a large number of records? We're not opposed to
> changing code, but if just a few H spec changes and/or compiling options
> could gain
> us a bit of performance, it would help us out.
> 
> I've tried a few of the basics (OPTIMIZE(*FULL), NoDEBUGIO, etc.) but
> didn't see much of a change in my benchmarks.
> 
> Thanks for any help
> 
> Jim Wiant
> 
> 
> Once a job is fouled up, anything done to improve it makes it worse. 
> Finagle 
> 
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