RE: Slow respond time when file change to open with

Mark and Lim,

Is it possible to save a little time by doing a SETLL and testing for an
exact match?  As I understand it, it would save time because the record
is not read into memory and then moved field by field to the program.
Then if there is an exact match a read will get the record into memory
and allow an update.

Just a thought, amoung the few I get far too seldom.

Marvin Rading

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Lim,

You mention the "only" logic change is for a chain to the outfile, then
update or write
as appropriate.  The time increase is right there, your disk I/O has
just
doubled, so has your time.
Record blocking cannot do much for you, since you now will update or
write a
record based upon
only one record at a time.  If you business requirements are forcing the
need to do the chain, and
do an update or add, then you are stuck with a longer running program -
those disk heads are very busy.
If you are flexible in your business requirements, change back to just
writing records.

HTH
Mark


-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx
[mailto:rpg400-l-bounces@xxxxxxxxxxxx]On Behalf Of Lim Hock-Chai
Sent: Wednesday, April 28, 2004 4:09 PM
To: rpg400-l@xxxxxxxxxxxx
Subject: Slow respond time when file change to open with update&Add


I created a RPG program that reads an input file that contains about 2.5
mil+ records and write them to a output file if they meeting the
criteria
(about 1.2 mil+ records).
 
1) It took about 35 mins to run when the input file is open as Input
only
with sequential access (No Key).  The output file is open as output
only.
2) It took about 70 mins to run when the program is change to open the
input
file as Input only with key access and the outfile as Update & Add.  The
only logic added to the program is it do a chain to outfile, if %found,
update, otherwise write.
 
I think the increase of processing time on 2 is cause the outfile open
as
Update&ADD, which cause the program to not do record blocking when write
to
outfile.
 
I got several methods in mind that I can think of that might speed up 2.
However, just wonder if anybody has had the same problem before and know
a
good method to speed it up.
 
thanks