Re: Performance problems with Java SOAP client

    Hi Andy,

    It's difficult to pinpoint things without knowing the application or
seeing the code.  And one of the problems with mailing lists and forums for
apps of any complexity is the catch 22 that we need code to be precise about
the problem, but the code is probably too long/involved for readers to put
in a ton of free time to analyze.

    What I can do is point to some areas that might be helpful.  My
assumption is that yours is a properly written multi-threaded app or that a
container is handling threading for you.

a)  Tuning Java:  Besides using OPTIMIZE(40), what else can we do ?

    Optimization is not necessarily helpful if it doesn't impact
bottlenecks.  You need to do some profiling or benchmarking to try to find
them.  While some designs are bad enough to require rewriting, doing that,
especially in a completely different language, won't help if the bottlenecks
are still there.  Once you've found them is when optimization should come
into play.

    Networks are unreliable by nature.  Check that you aren't having network
latency problems.  What are your customers comparing performance with?  Is
it slow all the time or does it get worse under load?  What else is running
on your machine?  Theirs?

    Ensure that you are using the latest/greatest SOAP implementation.

    Your COBOL program could be the problem.  Most AS/400 languages
don't really handle threading, but just run serially.  That's not language
bashing, just a fact to be aware of - see "Threads considerations for ILE
COBOL and RPG language" at

<http://publib.boulder.ibm.com/infocenter/iseries/v5r3/ic2924/info/rzahw/rza
hwileco.htm>

Is the COBOL program getting reloaded?  In the intermediate term, running
multiple copies that read from and respond to message or data queues may
improve things at the cost of more processing.

    In Chapter 14 "Making the Right Choices for SOAP Scability" of the book
"Java Testing and Design", Frank Cohen claims a huge improvement by
changing the SOAP encoding.  You might want to take a look.  The book is
available for free download at

<http://www.theserverside.com/books/prenticeHall/JavaTestingAndDesign/index.
tss>

    HTH somewhat,


                                                         Joe Sam

Joe Sam Shirah -        http://www.conceptgo.com
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----- Original Message -----
From: "Andres D'Aquila" <ad476@xxxxxxxxxxxxx>
To: <JAVA400-L@xxxxxxxxxxxx>
Sent: Sunday, July 18, 2004 9:53 PM
Subject: Performance problems with Java SOAP client


Hello !

Some of our customers want to use webservices on their ISeries (V5R2)
machines
We have made a Java SOAP client, but they say that the performance is
unacceptable.
The program is very simple:  it receives some data, calls some COBOL
program, and
returns some data.

We are exploring some ideas, and we would like to get some feedback of this
forum:

a)  Tuning Java:  Besides using OPTIMIZE(40), what else can we do ?

b)  Rewrite the program in some native language ( ILE C or ILE RPG):
     we know that there is a XML parser for procedural languages, but we
have not found
    a SOAP library.   Would it be complex to write our own SOAP routines ?
    We have some experience writing TCP programs, but not HTTP or SOAP
programs
    in these languages.

c) Get the Java client out of the Iseries:  the program still will handle
SOAP messages,
   but it will use TCP and plain messages to communicate with a ILE C
program
   in the Iseries.

I would appreciate your opinions and suggestions.

Thank you,


         Andy D'Aquila