Re: Suggestion for improving loop performance

Hello,

It would be hard to tell you the best performing method without actually
writing the code and benchmarking the alternatives. Here are ways to do
this:

1) Keep what you have.

2) Instead of SCAN into an array, try %SCAN in a loop. You could make
this all one loop that way.

3) Instead of using SCAN/%SCAN you could consider looping thru the
characters one-by-one -- also make it all one loop.

Check each of these methods to see which performs best.

Also, I would definitely eliminate the horrible %CHECKR -- this is a huge
time-waster. %TRIMR is no better. Instead, use a VARYING field so the
trimming/checking isn't needed.

-SK




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

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