Re: Indexes vs Logical Files -- MIDRANGE-L

Given recent reports I don't believe the jump to 7.5 and the performance
problems to be a coincidence. There is something going on with 7.5 that
IBM A) has not admitted to if they know what's wrong, or B) more likely
given the age of 7.5 something popped in with PTFs and there's an issue
with the optimizer.

Either way I'm confident it will get worked out, but painful in the
meantime.....

--
Jim Oberholtzer
Chief Technical Architect
Agile Technology Architects

On Mon, Oct 16, 2023 at 9:33 AM Greg Wilburn <
gwilburn@xxxxxxxxxxxxxxxxxxxxxxx> wrote:

Thanks Jim... I'm already there. We're on 7.5 and it seems the issues
started when we jumped there from 7.3 (could be a coincidence though).

I've had a case open since October 4. We've taken several data
collections, running job watcher, and dumped the plan cache.

Thx,
Greg

-----Original Message-----
From: MIDRANGE-L <midrange-l-bounces@xxxxxxxxxxxxxxxxxx> On Behalf Of Jim
Oberholtzer
Sent: Friday, October 13, 2023 4:31 PM
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxxxxxxxx>
Subject: Re: Indexes vs Logical Files

The 1tb is what I was considering, but if they have been rebuilt since
first created then it’s most likely not the problem.

The best bet is to get the performance tools turned on and do some
collections. With those tools you’ll (or IBM) will have somewhere to start
looking at the performance issues. I don’t recall the OS level you’re on
but starting a case with IBM won’t hurt. At least they will guide you to
what to consider.

Jim Oberholtzer
Agile Technology Architects
Office: 414-433-4363
Mobile: 414-915-1445
Sent from mobile device

On Oct 13, 2023, at 3:04 PM, Greg Wilburn <

gwilburn@xxxxxxxxxxxxxxxxxxxxxxx> wrote:

Thanks everyone for the suggestions!

Jim - what am I looking for? Some of my LF were created 20 years ago,

but likely compiled relatively recently.

OEBOX1 is a logical file.. DSPFD? Is this what you're referring to?

Access path . . . . . . . . . . . . . . . . : Keyed
Access path size . . . . . . . . . . . . . : ACCPTHSIZ *MAX1TB
Access path logical page size . . . . . . . : PAGESIZE *KEYLEN
Maximum key length . . . . . . . . . . . . : 36
Maximum record length . . . . . . . . . . . : 131
Keep in memory . . . . . . . . . . . . . . : KEEPINMEM *NO

Does this mean the page size is 36?

Charles - thanks for the explanation. The "Explain" portion in RSS is a

bit overwhelming for this SQL view. I worried about burying views within
views.

And you're right about trying it... sometimes the suggested indexes work

wonders, while other times they do very little.

Greg

-----Original Message-----
From: MIDRANGE-L <midrange-l-bounces@xxxxxxxxxxxxxxxxxx> On Behalf Of

Jim Oberholtzer

Sent: Friday, October 13, 2023 10:55 AM
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxxxxxxxx

Subject: Re: Indexes vs Logical Files

I believe at one time that was true. Since then the CQE has been

displaced by the SQE.

I would be looking at those logical files since they are most likely

older to see the page size (as some have suggested) and other attributes.
Might be worthy of a rebuild with newer parameters.

Jim Oberholtzer
Agile Technology Architects
Office: 414-433-4363
Mobile: 414-915-1445
Sent from mobile device

--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing

list

To post a message email: MIDRANGE-L@xxxxxxxxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: https://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxxxxxxxx
Before posting, please take a moment to review the archives
at https://archive.midrange.com/midrange-l.

Please contact support@xxxxxxxxxxxxxxxxxxxx for any subscription

related questions.

--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
To post a message email: MIDRANGE-L@xxxxxxxxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: https://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxxxxxxxx
Before posting, please take a moment to review the archives
at https://archive.midrange.com/midrange-l.

Please contact support@xxxxxxxxxxxxxxxxxxxx for any subscription related
questions.

--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
To post a message email: MIDRANGE-L@xxxxxxxxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: https://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxxxxxxxx
Before posting, please take a moment to review the archives
at https://archive.midrange.com/midrange-l.

Please contact support@xxxxxxxxxxxxxxxxxxxx for any subscription related
questions.