Re: Suggestion for improving loop performance

Two points:
1) Are you sure that the program is CPU bound?
2) When you compile the RPG, specify maximum optimization--I forget which keyword, unfortunately. In a former life we had a text processing programs with a lot of internal loops. When I recompiled it with optimization it *significantly* improved performance and reduced run time.

Sam

On 5/19/2015 1:17 PM, Singh, Ashwani (Lake Mary) wrote:

Folks,

We are trying to process a 69 million records file which is taking 5 hours plus to load into another file. (We have Block *Yes specified for the input file (with 69M records) We need to bring the processing down for sure..

We are trying for the multithread as well..

There are two crucial loops that run in this single program and causing trouble.

The first loop takes round about .6 seconds/rec processed the other one .4 seconds.

Our file is a flat file and is | delimited ..

Loop 1
D ARRAY1 S 5 0 DIM(999)
C '|' SCAN DATA ARRAY1
C Eval X= 1
C Eval A= 0
C Dow ARRAY1(X) > 0
C Eval A+=1
C Eval X+=1
C ENDDO

Loop2
C DOW A < #Pipesreq (Number of pipes actually required)
C Eval Fileds = %subst(fileds:1:%checkr(' ':Fileds)) + '|'
C eval A+=1
C ENDDO


Any suggestion will be highly appreciated..



Thanks,
Ashwani Singh