DB2 OPx question

Missy Case

DB2 OPx question
All,
Question 1) When DB2 writes trace data does it go to SMF via the OPx
buffers? Deduction 1) So when I get the DSNW133I messages about trace data
lost op1, that also affects my SMF data.

Question 2) Does DB2 roll through the OP1 - OP8 buffers like the active
logs? Deduction 2) So it stands to reason, if the op buffers roll & 1-8
are defaults & I have my monsize Zparm set to 51200 that's 50k times 8,
right? That's quite a bit to get that DSNW133 message that they're full
very often at all.

We had an issue last week that occurred precisely over the 3 & a half
minute period when trace data was lost! Yuck!

Anyhow - I was wondering if my deductions were correct, close or not in the
ballpark! The doc is a little cloudy on this issue.

Question 3) What's in use out there in the real world? or What settings
are on track for V7 datasharing (3 members) & a very busy online
transaction system.

As always, thanks for the input & updates!
Missy Case
PFDBA FDR
701-275-6358


-----------------------------------------
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.

---------------------------------------------------------------------------------
Welcome to the IDUG DB2-L list. To unsubscribe, go to the archives and home page at http://www.idugdb2-l.org/archives/db2-l.html. From that page select "Join or Leave the list". The IDUG DB2-L FAQ is at http://www.idugdb2-l.org. The IDUG List Admins can be reached at [login to unmask email] Find out the latest on IDUG conferences at http://conferences.idug.org/index.cfm

Joel Goldstein

Re: DB2 OPx question
(in response to Missy Case)
Missy,

SMF data does not go through the OPx buffers.
The Lost data msg has nothing to do with SMF data, it's only for that OPx
buffer.
If you are having a problem writing heavy volume to SMF, there will be a
message issued
indication SMF buffers are full (or something along this line, it's been a
while). After that,
if its really bad SMF might abend (used to, but not sure now). If that
happens, you have to re-ipl the whole system.
OPx buffers do not roll. Whatever buffer a specific trace is written for is
the only place it will go.
The actual size of the OPx buffer can be specified when a trace is started,
so it might be a lot larger than
the 50K in your zparm. We usually use a 4Meg buffer when starting high
volume traces.

Now one of the "gotchas" is that DB2 never releases that memory when the
trace is stopped.
This is a DB2 bug, and been there forever. Of course IBM does not consider
it a bug.

I'm not sure what you mean with Q3.

Regards,
Joel


----- Original Message -----
From: <[login to unmask email]>
Newsgroups: bit.listserv.db2-l
To: <[login to unmask email]>
Sent: Thursday, December 01, 2005 5:05 PM
Subject: [DB2-L] DB2 OPx question


> All,
> Question 1) When DB2 writes trace data does it go to SMF via the OPx
> buffers? Deduction 1) So when I get the DSNW133I messages about trace
> data
> lost op1, that also affects my SMF data.
>
> Question 2) Does DB2 roll through the OP1 - OP8 buffers like the active
> logs? Deduction 2) So it stands to reason, if the op buffers roll & 1-8
> are defaults & I have my monsize Zparm set to 51200 that's 50k times 8,
> right? That's quite a bit to get that DSNW133 message that they're full
> very often at all.
>
> We had an issue last week that occurred precisely over the 3 & a half
> minute period when trace data was lost! Yuck!
>
> Anyhow - I was wondering if my deductions were correct, close or not in
> the
> ballpark! The doc is a little cloudy on this issue.
>
> Question 3) What's in use out there in the real world? or What settings
> are on track for V7 datasharing (3 members) & a very busy online
> transaction system.
>
> As always, thanks for the input & updates!
> Missy Case
> PFDBA FDR
> 701-275-6358
>
>
> -----------------------------------------
> 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.
>
> ---------------------------------------------------------------------------------
> Welcome to the IDUG DB2-L list. To unsubscribe, go to the archives and
> home page at http://www.idugdb2-l.org/archives/db2-l.html. From that page
> select "Join or Leave the list". The IDUG DB2-L FAQ is at
> http://www.idugdb2-l.org. The IDUG List Admins can be reached at
> [login to unmask email] Find out the latest on IDUG conferences
> at http://conferences.idug.org/index.cfm
>
>

---------------------------------------------------------------------------------
Welcome to the IDUG DB2-L list. To unsubscribe, go to the archives and home page at http://www.idugdb2-l.org/archives/db2-l.html. From that page select "Join or Leave the list". The IDUG DB2-L FAQ is at http://www.idugdb2-l.org. The IDUG List Admins can be reached at [login to unmask email] Find out the latest on IDUG conferences at http://conferences.idug.org/index.cfm

Abe Kornelis

Re: DB2 OPx question
(in response to Joel Goldstein)
Missy,

you asked:

Question 1) When DB2 writes trace data does it go to SMF via the OPx buffers?
Nope. As Joel mentioned trace data goes where you tell it to go. That is,
either to SMF, GTF, or one of the OPxx-buffers.

Question 2) Does DB2 roll through the OP1 - OP8 buffers like the active logs?
See above.

Question 3) What's in use out there in the real world?
We use the OPxx buffers only for the online monitors. For most subsystems
there's a single 8K buffer. If trace data is lost, it's not that much of
an issue. In case we really need the lost data, we can go back to SMF
and extract the data from there...

Abe Kornelis
Technisch Specialist
Data Centers & Hosting Services
Getronics PinkRoccade
Fauststraat 1
7323 BA Apeldoorn
P.O. box 9105
7300 HN Apeldoorn
The Netherlands
M: +31 (0)6 4609 3353
T: +31 (0)55 577 8619
[login to unmask email]
www.getronicspinkroccade.nl
The information transmitted is intended only for use by the addressee and may contain confidential and/or privileged material. Any review, re-transmission, dissemination or other use of it, or the taking of any action in reliance upon this information by persons and/or entities other than the intended recipient is prohibited. If you received this in error, please inform the sender and/or addressee immediately and delete the material. Thank you.

---------------------------------------------------------------------------------
Welcome to the IDUG DB2-L list. To unsubscribe, go to the archives and home page at http://www.idugdb2-l.org/archives/db2-l.html. From that page select "Join or Leave the list". The IDUG DB2-L FAQ is at http://www.idugdb2-l.org. The IDUG List Admins can be reached at [login to unmask email] Find out the latest on IDUG conferences at http://conferences.idug.org/index.cfm

Max Scarpa

Re: DB2 OPx question
(in response to Abe Kornelis)
Missy

AFAIK:

1) DB2 writes its data in SMF or in other places according the
specifications you give when starting a trace (stat,accounting,performance
etc) in DEST parameter

2) There's no roll as log.You choose a buffer and data are writtenn there
as far as the trace is active.I think buffers are rewritten when full (As I
saw when playing with traces and OPx)

3) I've no answer for it. I use small buffers for my tests with REXX and
IFCIDs.

HTH

Max Scarpa

---------------------------------------------------------------------------------
Welcome to the IDUG DB2-L list. To unsubscribe, go to the archives and home page at http://www.idugdb2-l.org/archives/db2-l.html. From that page select "Join or Leave the list". The IDUG DB2-L FAQ is at http://www.idugdb2-l.org. The IDUG List Admins can be reached at [login to unmask email] Find out the latest on IDUG conferences at http://conferences.idug.org/index.cfm