| |
|
RSS Feed - WebSphere MQ Support
|
RSS Feed - Message Broker Support
|
  |
|
| System priorities between MQ DB2 and CICS |
« View previous topic :: View next topic » |
| Author |
Message
|
| fjb_saper |
 Posted: Sun Dec 14, 2008 4:59 am Post subject: System priorities between MQ DB2 and CICS |
 |
|
Grand High Poobah
Joined: 18 Nov 2003
Posts: 20756
Location: LI,NY
|
Guys, we have recently run into  problems  (running at 100% + CPU) and I need some help here as the Mainframe is an area I have little knowledge of.
For those of you who use DB2, CICS and MQ on the mainframe,
what system priorities have you assigned to:
- DB2
- batch programs running against DB2
- CICS
- MQMaster
- MQCHIN
Can you also please elaborate a little bit on the pros and cons of your priority allocation? Remember we are only seeing problems when running @ 100% + CPU.
Is it possible to run against DB2 with different priorities (online vs batch) or do all DB2 operations run with the same priority?
Is it possible to limit the DB2 resource usage (memory space and other stuff) for a specific program so as to leave room for CICS MQ Triggered stuff to squeeze their DB2 queries/updates in?
Thanks for your insight. 
_________________
MQ & Broker admin |
|
| Back to top |
|
 |
| bruce2359 |
| Posted: Sun Dec 14, 2008 2:59 pm Post subject: |
|
|
Poobah
Joined: 05 Jan 2008
Posts: 9469
Location: US: west coast, almost. Otherwise, enroute.
|
Exactly what symptoms are you seeing? Running at 100% cpu on zSeries hardware may or may not be a problem. For example: are you (your applicaitons) missing service-level agreements (SLAs)? What other symptoms (other than 100% cpu) are you experiencing?
Is the z/OS instance experiencing excessive paging rates? How much central storage (think RAM, but don't say RAM) is allocated to the LPAR where you see the symptoms? How many cpus are allocated to the LPAR?
Is WLM (WorkLoad Manager) running in the z/OS instance? If so, the as-delivered from the factory settings provide database accesses with highest priority, transactions next lower priority, everything else next lower priority. You will need to ask your mainframe techies where they have placed WMQ and other applicaitons in the priority scheme.
Mainframes have lots of tuning knobs, but lots of help to resolve performance issues in real-time (WLM). Performance tuning is more complicated on mainframes.
It isn't just priority. Mainframes are very different from Windows and UNIX platforms. You will need to find a mainframe technical person to help you understand this.
_________________
I like deadlines. I like to wave as they pass by.
ב''ה
Lex Orandi, Lex Credendi, Lex Vivendi. As we Worship, So we Believe, So we Live. |
|
| Back to top |
|
|
| fjb_saper |
| Posted: Sun Dec 14, 2008 7:36 pm Post subject: |
|
|
Grand High Poobah
Joined: 18 Nov 2003
Posts: 20756
Location: LI,NY
|
Symptoms:
It takes 30 mins to start a triggered channel.
The CPU is used up by the DB and there are simply no cycles for the CHIN that has a lower priority than DB2.
Of course with things like that SLA's of sub-second timing are missed big time!.
It started happening a few nights ago and we are all rackig our brains trying to understand what changed? All I can think of right now is the business changing some customer related processes from running in group A to run in group B.
Group A and B usually run at 10 to 15 days interval.
Thanks
_________________
MQ & Broker admin |
|
| Back to top |
|
|
| bruce2359 |
| Posted: Mon Dec 15, 2008 5:30 am Post subject: |
|
|
Poobah
Joined: 05 Jan 2008
Posts: 9469
Location: US: west coast, almost. Otherwise, enroute.
|
| Quote: |
| It started happening a few nights ago and we are all racking our brains |
What was the cpu utilization before this?
You will need to find out from your z/OS techies what changed, and which application(s) is/are using/abusing system resouces.
As to the pros and cons: it usually makes sense to have database accesses have the highest priority (access to system resources), then transactions that use those databases, then everything else (batch).
This is all tunable with WLM.
_________________
I like deadlines. I like to wave as they pass by.
ב''ה
Lex Orandi, Lex Credendi, Lex Vivendi. As we Worship, So we Believe, So we Live. |
|
| Back to top |
|
|
|
|
|
| |
|
Page 1 of 1 |
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
|
|
|
