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

["Kurt Anderson" <kjanderson@xxxxxxxxxxxxx>]

Rory,

Thanks for the followup.  (Once I started looking into it I realized the
block I had specified was in SQL Fetch statements, not the actual
override you mention.) 


Kurt Anderson
Application Developer
Highsmith Inc

-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx
[mailto:rpg400-l-bounces@xxxxxxxxxxxx] On Behalf Of Hewitt, Rory
Sent: Wednesday, November 30, 2005 1:02 PM
To: rpg400-l@xxxxxxxxxxxx
Subject: RE: RE: Optimizing File I-O in RPG IV/ I-Series

Kurt wrote:

>Nevermind... Just saw Rory's followup email.

Kurt, I should have said that the ODP buffer size on RISC boxes is 128K
(rather than the 32K used on CISC boxes). OS/400 only uses the first 4K
of the buffer when it does its default blocking, so they 'waste' 124K of
usable buffer space on a RISC box...!
 
Therefore you should use:
 
OVRDBF...SEQOBLY(*YES blocking-number)
 
where blocking-number = (131072 / physical-file-record-length) and round
that down. Of course the IBM article explains it much better than me
(including the fact that
 
HTH,
 
Rory