Re: AS/400 and Java

["Mike Silvers" <msilvers@xxxxxxxxxxx>]

Dieter,

Do not use CRTJVAPGM???  When a Java program is run, the system
automatically does the CRTJVAPGM if one has not been done before.  I think
that you should look at the command defaults and adjust them accordingly to
get the best performance in the CRTJVAPGM command...

Do not mix Java with RPG or COBOL????  Performance depends on the method of
interaction.  I think such a blanket statement is overstated.  I agree that
direct program calls are expensive, but other methods (such as Socket/XML
processing) do not significantly degrade the performance.  I have found that
it is faster to use a socket to communicate with an RPG program and do
database access than using JDBC with Java.

Mike


----- Original Message -----
From: "Scott Johnson" <sjohnson@highsmith.com>
To: <java400-l@midrange.com>
Sent: Monday, November 04, 2002 9:39 AM
Subject: Re: AS/400 and Java


>
> Dieter,
>
> In reference to number 2, are you saying to NOT use CRTJVAPGM on a V5R1 or
> V5R2 box? Can you please tell me why?
>
> Thanks,
>    Scott P. Johnson
>
> > To: java400-l@midrange.com
> > Subject: Re: AS/400 and Java
> > From: Dieter.Bender@t-online.de
> > Date: Mon, 04 Nov 2002 11:49:38 +0100 (CET)
> > Reply-To: java400-l@midrange.com
> >
> > Hi,
> >
> > and here my performance tips:
> >
> > 1. read the recent manuals (Performance Capabilities Reference
> > recommends the JIT environment since V4R5!)
> > 2. don't use CRTJVAPGM on boxes > V4R5
> > 3. don't use the native driver, its buggy, use the latest Toolbox
> > driver
> > 4. don't use record level access (more IO Operations compared to SQL)
> > 5. run your application server on inexpensive boxes (Wintel, or Linux
> > on Intel), if possible (scalability)
> > 6. Don't mix Java with RPG and/or COBOL, the context change is very
> > expensive
> > 7. use all features of the as400 as database server, you've paid for
> > it
> > 8. for maximal speed with minimal hardware requirements use assembler
> > and shift your bytes bit by bit
> >
> > Dieter
>
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