RE: Records written to a file don't show up immediately

Actually, forgot an option.

You can just specify the BLOCK(*NO) keyword on the f-spec.


Charles


> -----Original Message-----
> From: Wilt, Charles 
> Sent: Monday, September 27, 2004 11:10 AM
> To: rpg400-l@xxxxxxxxxxxx
> Subject: RE: Records written to a file don't show up immediately
> 
> 
> My understanding:
> 
> Prior to v5r2, FEOD actually force the records to be written 
> out to disk.
> 
> At v5r2, the 'N' operation extender was added that causes the 
> records to be
> written out to the DB from the buffer but does not 
> necessarily cause the
> records to be written to disk.
> 
> So FEOD was pretty "expensive", but with the new extender 
> it's not so much.
> 
> However, FRCRATIO itself is concerned about writing to disk 
> instead of just
> the DB.  So it should be just as expensive as FEOD w/o the extender.
> 
> To the original poster, as other have said, the problem is 
> that RPG buffers
> the writes to the DB.  This is fine with a batch program, but for an
> interactive program you should really turn the buffer off.  
> The way to do
> this is simply to use:
> OVRDBF SEQONLY(*NO)
> 
> 
> There was a rather detailed discussions about RPG and 
> buffering not to long
> ago:
> http://archive.midrange.com/rpg400-l/200408/msg00302.html
> 
> In particular check out this link to an IBM Technote of the subject:
> http://www-1.ibm.com/support/docview.wss?uid=nas1d6738e1cd37e1
> f33862565c2007
> cef79&rs=110
>  or
> http://tinyurl.com/47y5r
> 
> >From the technote:
> Interactive - To match the size of an interactive screen (presumes the
> application presents eight records on a screen) one set of 
> data presented to
> a user interactively (SEQONLY *YES 8). Most interactive 
> applications' writes
> are probably best coded as immediate writes (SEQONLY *NO). An 
> alternative
> commonly mentioned is to use the FEOD operation to force the 
> buffer (and
> while this does force the writes to the database, it also 
> causes the data to
> be forced to secondary storage (DASD) and makes it likely 
> that the page on
> which the data resides will be stolen). FEOD is almost always 
> less efficient
> from a system-wide perspective than using single writes. 
> 
> (note: I think they are talking FEOD w/o the extender here)
> 
> 
> Come to think of it Dan, you had some posts in that discussion....
> 
> HTH,
> Charles
> 
> 
> > -----Original Message-----
> > From: Dan Bale [mailto:dbale@xxxxxxxxxxxxx]
> > Sent: Monday, September 27, 2004 10:24 AM
> > To: RPG programming on the AS400 / iSeries
> > Subject: RE: Records written to a file don't show up immediately
> > 
> > 
> > It was my impression that FEOD is relatively expensive, 
> > especially if you're
> > doing it after every record being output.  Well, perhaps for 
> > an interactive
> > program it may be acceptable.
> > 
> > > FRCRATIO will work but is also
> > > easier to change by more people....
> > 
> > Hmmmph.  Don't know why that is.  Well, then, stick the 
> > override in the RPG
> > program.
> > 
> > > -----Original Message-----
> > > From: rpg400-l-bounces@xxxxxxxxxxxx / Holden Tommy
> > > Sent: Monday, September 27, 2004 9:47 AM
> > >
> > > FEOD is what I prefer in this case.  the FRCRATIO will work 
> > but is also
> > > easier to change by more people....
> > >
> > > Thanks,
> > > Tommy Holden
> > 
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