Re: Speed issues?

["Bruce Jin" <JIN007M@xxxxxxxxxxx>]

 It is strange to me that data retrieval would take more than a few seconds.
We have built applications that run on many machines: big or small AS400s
(v4r4, v4r5, v5r1), PCs, and Linux. They all use Toolbox to connect to DB2
either locally or remotely. For database record access and calling RPG etc.
we almost always use JDBC directly. We used JDK 1.1, 1.2, 1.3, 1.4. I seldom
see response time exceeds 1 (one) second even some of the applications have
many file accesses.
I would check the following:

1. Connection object is pooled correctly. (a single connection may take up
to 1 second).

2. SQL syntax. I had a file with 1.5 million records. Add Optimization For
clause cut down response time from 10 seconds to under 1.

3. As people suggested, check the toolbox. I was playing the AS400 class
from toolbox and a record access took 15 seconds! I suspect that was because
the jt400.jar file got messed up on that box. Now I only use jt400 to do the
connection.

4. Try to use JDBC for record access and see what happens.

Bruce

Web Applications written in Java servlet and RPG/cgi
http://www.crazybikes.com/employees/I00200GC.mrc

Servlet: write once, deploy on any platform and access any database:
http://www.mrc-productivity.com/products/demo2.html


----- Original Message -----
From: "Robert Upshall" <rupshall@psasoft.com>
To: <java400-l@midrange.com>
Sent: Thursday, July 11, 2002 8:16 AM
Subject: Re: Speed issues?


> We built/tested it on our machine, a 820 FC 2395, CPW is 35 Interactive
and
> 370 in batch, DASD Utilization is about 35%.  We have also tried it on a
> couple customer machines, I'll try and get those numbers, but the results
> were more or less the same.
>
> JDK version is 1.3.1, toolbox is whatever version is shipped with VAN
3.5.3.
>
> The application does allot of things, basically I will load a JList from a
> customer DB2 file on the as400, then based on who was select do a key
lookup
> with KeyedFile, maybe to 1 or more files depending on the situation.
>
> From my experience it will take 3 or 4 seconds to do a KeyedFile type
chain,
> and exponentially longer to read a set of records.
>
> I have also noticed that a program call has much faster access than a
> records access, for example.
>
>     if I have key1 for file1, if I open a KeyedFile and position based on
> key1 it will
>     take a 2 or 3 seconds,
>
> but
>
>     if I write an rpg pgm that accepts a key, then uses than key to do a
rpg
> chain and
>     return a field it works almost instantaneously
>
> Both methods above use the same key to access the same record, the program
> call has the extra step of a rpg program in the middle but yet it runs
> noticeably faster.
>
> The program call method works well if I want to take a customer number and
> lookup a customer name, but when I need to read a dynamic record set the
pgm
> method.
>
> I guess this leads to me answering the question of what I expect, I
expected
> a response time closer to the pgm call speed rather than the RLA speeds.
>
> Hope I provided the answers you were looking for,
> Robert
>
>
> ----- Original Message -----
> From: "Joe Pluta" <joepluta@PlutaBrothers.com>
> To: <java400-l@midrange.com>
> Sent: Thursday, July 11, 2002 9:47 AM
> Subject: RE: Speed issues?
>
>
> > > From: Robert Upshall [mailto:rupshall@psasoft.com]
> >
> > > I have been creating a system that uses "AS400 Toolbox For Java".  The
> > > system is a GUI front-end runs on a pc and uses the toolbox connection
> > > classes to access DB2 files and RPG programs.
> >
> > > Currently they seem to run allot slower that I expected.
> >
> > Robert, how about some numbers?  What size 400 are you running?  What
CPW,
> > and what percentage utilization?  What is your application doing?  How
> many
> > I/O's?  JDBC or RLA?  Calls to RPG programs?  What is your response
time?
> > How big of a PC (CPU speed, memory)?  What version of the JDK?  What
> version
> > of the toolbox?  And most importantly, what do you expect?
> >
> > Joe
> >
>