Hello, 

I inherited several really old Mainframe Queue Managers and the Page Sets are allocated very small. 
I was thinking of just resizing the existing Page Sets to 1 Gig Extended and cleaning up the Storage Classes. 
My reason for this is that I will have one less then to worry about. 

My question is what are the negatives with me doing this? Will I see performance issues? Etc?

I appreciate any feedback  :)


Thanks,
Michael

------------------------------
Michael Pearson
------------------------------

Hi Michael,

There shouldn't be any performance issues during normal queue manager operations. But having a larger page set will mean that backups take longer and use up more space. Recovering from failure will take longer too.

As you say, the plus point is that you are less likely to run out of space.

Don't forget to look at your buffer pools sizings, and mappings too.

------------------------------
MATTHEW LEMING
------------------------------

Original Message:
Sent: Mon July 18, 2022 09:50 AM
From: Michael Pearson
Subject: zMQ 9.1 LTS - Oversizing Page Sets to 1 Gig

Hello, 

I inherited several really old Mainframe Queue Managers and the Page Sets are allocated very small. 
I was thinking of just resizing the existing Page Sets to 1 Gig Extended and cleaning up the Storage Classes. 
My reason for this is that I will have one less then to worry about. 

My question is what are the negatives with me doing this? Will I see performance issues? Etc?

I appreciate any feedback  :)


Thanks,
Michael

------------------------------
Michael Pearson
------------------------------

Good stuff  Matt... plus

You have not had a problem up till now - otherwise the page set would have expanded.
You can set up pageset expansion so it occurs "just before it is needed".  This can expand up to 123 ( I think) extensions.

With bigger buffer pools, you'll need more real storage to map it to (and possibly bigger z/OS page sets) so talk to the z/OS sysprogs.  During a test I managed to make a buffer pool so big, z/OS ran out of virtual storage and I had to re-ipl!
Although you can dynamically make a buffer pool bigger, you do not want to suddenly find you have a z/OS constraint.

A page set backup does a backup of all pages - even if the pages are not being used.
You can use the hardware to do a "snap" backup, which basically creates a backup by copying the pointers to the pages in the DASD control unit.
As a page is changed - it gets a new physical page.  See  Do I need Concurrent Copy to backup my pagesets or can I use Fastreplication and save CPU?
This makes it an efficient use of the storage within the DASD subsystem.

Colin

------------------------------
Colin Paice
------------------------------

Original Message:
Sent: Tue July 19, 2022 04:07 AM
From: MATTHEW LEMING
Subject: zMQ 9.1 LTS - Oversizing Page Sets to 1 Gig

Hi Michael,

There shouldn't be any performance issues during normal queue manager operations. But having a larger page set will mean that backups take longer and use up more space. Recovering from failure will take longer too.

As you say, the plus point is that you are less likely to run out of space.

Don't forget to look at your buffer pools sizings, and mappings too.

------------------------------
MATTHEW LEMING

Original Message:
Sent: Mon July 18, 2022 09:50 AM
From: Michael Pearson
Subject: zMQ 9.1 LTS - Oversizing Page Sets to 1 Gig

Hello, 

I inherited several really old Mainframe Queue Managers and the Page Sets are allocated very small. 
I was thinking of just resizing the existing Page Sets to 1 Gig Extended and cleaning up the Storage Classes. 
My reason for this is that I will have one less then to worry about. 

My question is what are the negatives with me doing this? Will I see performance issues? Etc?

I appreciate any feedback  :)


Thanks,
Michael

------------------------------
Michael Pearson
------------------------------

In case it helps, you may find the recent feature in MO71 helpful to view all those queue -> storage class -> pageset -> buffer pool mappings.

Viewing Object Relationships in MO71

Cheers,
Morag

------------------------------
Morag Hughson
MQ Technical Education Specialist
MQGem Software Limited
Website: https://www.mqgem.com
------------------------------

Original Message:
Sent: Mon July 18, 2022 09:50 AM
From: Michael Pearson
Subject: zMQ 9.1 LTS - Oversizing Page Sets to 1 Gig

Hello, 

I inherited several really old Mainframe Queue Managers and the Page Sets are allocated very small. 
I was thinking of just resizing the existing Page Sets to 1 Gig Extended and cleaning up the Storage Classes. 
My reason for this is that I will have one less then to worry about. 

My question is what are the negatives with me doing this? Will I see performance issues? Etc?

I appreciate any feedback  :)


Thanks,
Michael

------------------------------
Michael Pearson
------------------------------

Thanks to all of you for the feedback. I'll put a plan together and get implemented. I wanted to check with the experts first before, "My fix today becomes tomorrow's problem". My coworker says that all the time. lol   

all the best, 
Michael

------------------------------
Michael Pearson
------------------------------

Original Message:
Sent: Mon July 18, 2022 09:50 AM
From: Michael Pearson
Subject: zMQ 9.1 LTS - Oversizing Page Sets to 1 Gig

Hello, 

I inherited several really old Mainframe Queue Managers and the Page Sets are allocated very small. 
I was thinking of just resizing the existing Page Sets to 1 Gig Extended and cleaning up the Storage Classes. 
My reason for this is that I will have one less then to worry about. 

My question is what are the negatives with me doing this? Will I see performance issues? Etc?

I appreciate any feedback  :)


Thanks,
Michael

------------------------------
Michael Pearson
------------------------------