Re: NBRRCDS and BLOCK(*YES)

["Uma Balasubramanian" <Uma_Balasubramanian@xxxxxxxxxxxxxxx>]

thanks to all of you who responded and gave a valuable feedback.

1) Yes my intention is to improve performance
2) I am using a 'Multi format Logical File' having 3 million records and
record length is 3768 (sorry its not a join logical) with 6 record foramats
from 6 files
The file is declared as a 'Primary and Update' file and update operations
are being performed.
3) The key of the multi format logical file is a single field PNO and is
same as the physical files in 4 cases. In 2 other case, the physical file
has one more field in the key apart from having PNO as the first field in
the key
4) I am not able to take out the K as the file is keyed
5) Since the file is in update mode, block(*yes) is not helpful
6) Original program was called froma CL using an OVRDBF on this file with
NBRRCDS as 3
7) I tried increasing 3 to 100 and observed performance gain (tested for
1300 records and observered performance gain from 3 minutes 40 seconds to 1
minute 3 seconds)

8) Now my worry is, where ever I refer to NBRRCDS details it mentions that
" if the file is processed by a keyed order, then the physical order of
data should be same as the keyed order else NBRRCDS will worse the
performance"
a) How do I know what is the physial order of data. (I dont understand
this)
b) How to find out what should be the value of NBRRCDS, if the physical
order of data (that I find after receiving feedback from you all) is the
same as the keyed order.

thanking you in advance.
Wish you all a Merry Christmas






"Booth Martin" <Booth@MartinVT.com>@midrange.com on 12/23/2002 10:12:16 PM

Please respond to rpg400-l@midrange.com

Sent by:  rpg400-l-admin@midrange.com


To:   <rpg400-l@midrange.com>
cc:

Subject:  Re: NBRRCDS and BLOCK(*YES)

 NBRRCDS(3)??  a very small file?

What is it you are looking for? Performance improvements?  Have you taken
out the K?

My experience with Block(*yes) was a revelation.  It provided close to 70%
reduction in processing time in two different applications.  I was
astounded




---------------------------------------------------------
Booth Martin   http://www.MartinVT.com
Booth@MartinVT.com
---------------------------------------------------------

-------Original Message-------

From: rpg400-l@midrange.com
Date: Monday, December 23, 2002 06:58:54
To: rpg400-l@midrange.com
Subject: NBRRCDS and BLOCK(*YES)

Hello Everybody,

Can anyone clarify me regarding:

My programs uses a file in update and primary mode. The file is a join
logical file. All records being read in processed and updated.
Record length is 3768

"1) Can I specify NBRRCDS or BLOCK(*yes)
2) If I specify NBRRCDS(3) in OVRDBF and specify BLOCK(*yes) in F specs for
the same file, which will be effective ?
3) Which one is beneficial.

thank you in advance

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