Re: AS400/i5 etc general behaviour

Hi, David:

In addition to IBM manuals mentioned by others, I recommend these Redbooks:
GG24-3723-02 AS/400 Performance Management Version 3 Release 1 (Redbook)
http://www.astradyne-uk.com/manuals/ir007310.pdf
GG24-4735 AS/400 Performance Management V3R6-V3R7 (Redbook)
http://www.redbooks.ibm.com/abstracts/sg244735.html?Open

They are available for free download on the web and contain excellent information and advice.

Also, here are some recommended books that may help:

_Mastering AS/400 Performance_ by Alan Arnold, Charly Jones, Jim Stewart, Rick Turner
http://www.mc-store.com/5824.html

_iSeries and AS/400 Work Management_ by Chuck Stupka http://www.mc-store.com/5023.html
_Supercharging the AS/400 - a guide to performance management_ by Ron Fielder and Carolyn Machell
(c) 1995 McGraw-Hill Book Company, ISBN 0-07-707997-3
(this book is /out of print/ so you will have to find it at used bookstores online, such as www.abebooks.com)

Hope that helps,

Mark S. Waterbury

> David FOXWELL wrote:

David FOXWELL wrote:

Hi,

I wondered if I could start a new thread using Alan's reply to the dataq problem.

----- Original Message -----
From: "Alan Campin" <alan0307d@xxxxxxxxx>
To: "Midrange Systems Technical Discussion"
<midrange-l@xxxxxxxxxxxx>
Subject: Re: Multiple Jobs reading from same data queue-who's turn is it?Job swapping.

If a job is sitting and waiting and gets no activity it is going to swap out to disk and when the request comes in it goes to the job and the job is not available so it swaps it back in memory which takes time. Same problem you run into with Client Access SQL jobs. User stops to take check a figure and when they come back and make another call, the job has been swapped and now they have to wait for it to get swapped back. On a very heavily load system, it is a really big problem.


On a general note :
Alan, how do you get to learn this kind of thing? I'd like to know more about how the system functions, for example, how a program is activated or shared.

As for the example above, I thought that the unique storage address meant that you never knew if main or secondary storage was being used. How would you know for sure that a job got swapped out to disk? Is this information recorded somewhere? How can you manage it? I'm thinking of a program that we have that uses an SQL request that functions normally then suddenly takes a long time to execute.