AS400 Performance Upgrade

[wink]IBM has proposed that we upgrade from a 2-way to a 4-way processor along with adding 4 additional gig memory totalling 10gb. We have been experiencing response time problems when the batch processing load increases. We usually have 150 users active at peak time on 5 citrix servers. We have been live for year.
I am looking to find anyone with similiar experience who have made the transition from a 2-way to 4-way. Did you find it worth the money?

Add a $5,000 Intel server or two. In my experience, the AS/400 boxes just do not do UBEs well (save the Holy War Flames). I firmly believe that scaling out instead of up will give you more bang for the buck.

There are other things to look at before spending that money. Do you have
JDE running in it's own system pool yet? Also, what do you have your System
Pools Max Actives set to? We had a lot of trashing going on until we got
some good advice and learned from experience, what levels to keep them at.
(it's different for every system) Also, how do you have your memory
distributed between *machine, *base , *spool, *interact? Do you have the
system set to auto tune or are you doing the adjusting? maybe you've
already gone down this road but if not you'll want to make sure you've tuned
your system at this level to it's maximum performance before you throw money
at it.

Darrell Allison
Systems Programmer
AS/400 V4R4 9406-730 8-Way / OneWorld B7332 SP11.3

To Darrel Allison:

You mentioned autotune in your email and doing your own tuning. What was
your experience with using autotune? Are there any particular downfalls you
found in using autotune on an AS/400 running XE?

Thanks,

OW XE update 4, SP 19
JAS, Terminal Serve

You only have a 2-way with 150 users? Ouch! We started out, and continue to use a 4-way with 4 gig ram. Started with 75 gig DASD, but have upgraded DASD to now 190 gig. Our only performance issue is with payroll. Other than that, all other UBEs seem to run relatively quickly.

I'm not yet on Xe, but on B7332 Sp11.3 and earlier I found that Autotune was driving my MAX Active figures on each System Pool too high. At one point *Base and *Interact were being driven above 500 and the system was just thrashing. (no one job getting enough time to complete without excessive swapping). I now keep these well below 50 and have seen big improvements in performance. Keep in mind everyones shop is unique and these settings may not give you the same results. Go Perform and use the performance tools, get to know how your system looks with these tools and get to know what 'High Volume', 'High Response Time' means on your system. Then use the Advisor and see what it Recommends. Use WRKSYSSTS and see if you ever have any Wait to Ineligable time. If not you're probably not using all your available memory. This isn't the Science in Computer Science, it's kind of touchy feelly and the only way to get comfortable with it is dig in and ask IBM, JDE, and the list a lot of questions about what you're finding really means. A couple of performance classes doesn't hurt either.

34 *BASE
46 *SPOOL
23 *SHRPOOL1
10 *INTERACT

I agree with Brother of Kara. Good to see that others share my experience and views.

I agree with B o K. I have found that that AS/400 is the most "User
Friendly" data base server but not the fastest. When I have added the
NT/2000 application/batch server on the side of it, I get the best
performance and reliability.


AM








Consultant with clients
at B7331 - Xe
Various Deployment Servers, Citrix and JAS

Look at your kernels first. It has been my experience that 1 out of 3 times, there aren't enough network and call object kernels configured.

How many do you have of each?

Good point. I had assumed that all tweaks were done. If not, here is a guideline:



Kernel Def #6
max

1 per 4/5 users

also ensure maxkernel processes is greater than total

If you increase your call Object Kernels, be sure to increase your network kernels (JDENET_N)
by a ratio of 4 Call Objects to 1 JDENET. The ini setting is MAX_NET_PROCESSES.

An example might be 96 Users = 16 Object Kernels = 4 JDENET_N kernels.

I don't quite understand what you meant. Please elaborate.

we have never modified the ini file on the AS400 and we would really much to improve performance especially in UBE execution time as well as Server Full Package build time. We found Server Full Package build to lengthy.