Quick question on OUTBUFF parameter Z/OS DB2 V8 (for Missy Case)

Richard Humphris

Quick question on OUTBUFF parameter Z/OS DB2 V8 (for Missy Case)
Hi Missy,

I wonder what the total number of pages you had in your buffer pools (on
system you decided 200000K was a good number). I'm thinking for my big
subsystem a outbuff of 200000k is about 4% of the size of my buffer
pools.

And as for loads, I'm thinking there may be a ratio between size of
buffer pools and the size of OUTBUFF that may be a good number to use.
So I'm curious as what your numbers are like.

Thanks,
Richard Humphris

-----Original Message-----
From: DB2 Data Base Discussion List [mailto:[login to unmask email] On
Behalf Of Case, Missy J.
Sent: Monday, December 03, 2007 11:44 AM
To: [login to unmask email]
Subject: Re: [DB2-L] Quick question on OUTBUFF parameter Z/OS DB2 V8

We ran a test in V7 to establish a good setting for our outbuff parm.
We run some very large conversions, and found that a very large outbuff
, say 200000 cut our conversion i.e. load elapsed times almost in half
at about 200000, you start to hit a diminishing return value for your
memory cost, so most of our prod systems are set at 200000k. Our
philosophy, if it's that cheap (relatively) then it's more than worth
the wall time we saved doing these massive projects......

Just to throw another monkey wrench into your discussion......


Missy Case
SYSDB DB2 Performance DBA
701-275-6358

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Missy J. Case

Re: Quick question on OUTBUFF parameter Z/OS DB2 V8 (for Missy Case)
(in response to Richard Humphris)
Richard,
We have many pools (more than Joel says most shops should have!) 25 4k
pools taking up 750000 4k pages.


Missy Case
SYSDB DB2 Performance DBA
701-275-6358

-----Original Message-----
From: DB2 Data Base Discussion List [mailto:[login to unmask email] On
Behalf Of Humphris,Richard P.
Sent: Thursday, December 13, 2007 3:32 PM
To: [login to unmask email]
Subject: Re: [DB2-L] Quick question on OUTBUFF parameter Z/OS DB2 V8
(for Missy Case)

Hi Missy,

I wonder what the total number of pages you had in your buffer pools (on
system you decided 200000K was a good number). I'm thinking for my big
subsystem a outbuff of 200000k is about 4% of the size of my buffer
pools.

And as for loads, I'm thinking there may be a ratio between size of
buffer pools and the size of OUTBUFF that may be a good number to use.
So I'm curious as what your numbers are like.

Thanks,
Richard Humphris

-----Original Message-----
From: DB2 Data Base Discussion List [mailto:[login to unmask email] On
Behalf Of Case, Missy J.
Sent: Monday, December 03, 2007 11:44 AM
To: [login to unmask email]
Subject: Re: [DB2-L] Quick question on OUTBUFF parameter Z/OS DB2 V8

We ran a test in V7 to establish a good setting for our outbuff parm.
We run some very large conversions, and found that a very large outbuff
, say 200000 cut our conversion i.e. load elapsed times almost in half
at about 200000, you start to hit a diminishing return value for your
memory cost, so most of our prod systems are set at 200000k. Our
philosophy, if it's that cheap (relatively) then it's more than worth
the wall time we saved doing these massive projects......

Just to throw another monkey wrench into your discussion......


Missy Case
SYSDB DB2 Performance DBA
701-275-6358

E-MAIL CONFIDENTIALITY NOTICE: The contents of this e-mail message and
any attachments are intended solely for the
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this message has been addressed to you in error, please immediately
alert the sender by reply e-mail and then delete this message and any
attachments. If you are not the intended recipient, you are notified
that any use, dissemination, distribution, copying, or storage of this
message or any attachment is strictly prohibited.

The IDUG DB2-L Listserv is only part of your membership in IDUG. DB2-L
list archives, the FAQ, and delivery preferences are at
http://www.idug.org/lsidug under the Listserv tab. While at the site,
you can also access the IDUG Online Learning Center, Tech Library and
Code Place, see the latest IDUG conference information, and much more.
If you have not yet signed up for Basic Membership in IDUG, available at
no cost, click on Member Services at http://www.idug.org/lsms

-----------------------------------------
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Richard Humphris

Re: Quick question on OUTBUFF parameter Z/OS DB2 V8 (for Missy Case)
(in response to Missy J. Case)
Very interesting. Thanks for the information.

Richard Humphris


-----Original Message-----
From: DB2 Data Base Discussion List [mailto:[login to unmask email] On
Behalf Of Case, Missy J.
Sent: Thursday, December 13, 2007 9:32 PM
To: [login to unmask email]
Subject: Re: [DB2-L] Quick question on OUTBUFF parameter Z/OS DB2 V8
(for Missy Case)

Richard,
We have many pools (more than Joel says most shops should have!) 25 4k
pools taking up 750000 4k pages.


Missy Case
SYSDB DB2 Performance DBA
701-275-6358

-----Original Message-----
From: DB2 Data Base Discussion List [mailto:[login to unmask email] On
Behalf Of Humphris,Richard P.
Sent: Thursday, December 13, 2007 3:32 PM
To: [login to unmask email]
Subject: Re: [DB2-L] Quick question on OUTBUFF parameter Z/OS DB2 V8
(for Missy Case)

Hi Missy,

I wonder what the total number of pages you had in your buffer pools (on
system you decided 200000K was a good number). I'm thinking for my big
subsystem a outbuff of 200000k is about 4% of the size of my buffer
pools.

And as for loads, I'm thinking there may be a ratio between size of
buffer pools and the size of OUTBUFF that may be a good number to use.
So I'm curious as what your numbers are like.

Thanks,
Richard Humphris

-----Original Message-----
From: DB2 Data Base Discussion List [mailto:[login to unmask email] On
Behalf Of Case, Missy J.
Sent: Monday, December 03, 2007 11:44 AM
To: [login to unmask email]
Subject: Re: [DB2-L] Quick question on OUTBUFF parameter Z/OS DB2 V8

We ran a test in V7 to establish a good setting for our outbuff parm.
We run some very large conversions, and found that a very large outbuff
, say 200000 cut our conversion i.e. load elapsed times almost in half
at about 200000, you start to hit a diminishing return value for your
memory cost, so most of our prod systems are set at 200000k. Our
philosophy, if it's that cheap (relatively) then it's more than worth
the wall time we saved doing these massive projects......

Just to throw another monkey wrench into your discussion......


Missy Case
SYSDB DB2 Performance DBA
701-275-6358

E-MAIL CONFIDENTIALITY NOTICE: The contents of this e-mail message and
any attachments are intended solely for the
addressee(s) and may contain confidential and/or legally privileged
information. If you are not the intended recipient of this message or if
this message has been addressed to you in error, please immediately
alert the sender by reply e-mail and then delete this message and any
attachments. If you are not the intended recipient, you are notified
that any use, dissemination, distribution, copying, or storage of this
message or any attachment is strictly prohibited.

The IDUG DB2-L Listserv is only part of your membership in IDUG. DB2-L
list archives, the FAQ, and delivery preferences are at
http://www.idug.org/lsidug under the Listserv tab. While at the site,
you can also access the IDUG Online Learning Center, Tech Library and
Code Place, see the latest IDUG conference information, and much more.
If you have not yet signed up for Basic Membership in IDUG, available at
no cost, click on Member Services at http://www.idug.org/lsms

-----------------------------------------
The information in this message may be proprietary and/or
confidential, and protected from disclosure. If the reader of this
message is not the intended recipient, or an employee or agent
responsible for delivering this message to the intended recipient,
you are hereby notified that any dissemination, distribution or
copying of this communication is strictly prohibited. If you have
received this communication in error, please notify First Data
immediately by replying to this message and deleting it from your
computer.

The IDUG DB2-L Listserv is only part of your membership in IDUG. DB2-L
list archives, the FAQ, and delivery preferences are at
http://www.idug.org/lsidug under the Listserv tab. While at the site,
you can also access the IDUG Online Learning Center, Tech Library and
Code Place, see the latest IDUG conference information, and much more.
If you have not yet signed up for Basic Membership in IDUG, available at
no cost, click on Member Services at http://www.idug.org/lsms

E-MAIL CONFIDENTIALITY NOTICE: The contents of this e-mail message and any attachments are intended solely for the
addressee(s) and may contain confidential and/or legally privileged information. If you are not the
intended recipient of this message or if this message has been addressed to you in error, please
immediately alert the sender by reply e-mail and then delete this message and any attachments. If you
are not the intended recipient, you are notified that any use, dissemination, distribution, copying, or
storage of this message or any attachment is strictly prohibited.

The IDUG DB2-L Listserv is only part of your membership in IDUG. DB2-L list archives, the FAQ, and delivery preferences are at http://www.idug.org/lsidug under the Listserv tab. While at the site, you can also access the IDUG Online Learning Center, Tech Library and Code Place, see the latest IDUG conference information, and much more. If you have not yet signed up for Basic Membership in IDUG, available at no cost, click on Member Services at http://www.idug.org/lsms