| Author |
Message
|
| KIT_INC |
 Posted: Wed Sep 15, 2010 4:47 am Post subject: How long will ZOS CHIN keep the queue open? |
 |
|
Knight
Joined: 25 Aug 2006
Posts: 589
|
| We are running MQ V7 on ZOS. We noticed that a cluster local queue is held open by the CHIN even when there is no message arriving. We understand that the CHIN will probably keep the open handle for while before releasing the queue. We have a need to delete and re-define the queue in a very short production maintenance window (5 minutes). If the queue is held open by the CHIN, we will not be able to delete it. We cannot stop the channel because it will impact other applications. We like to know how long will the CHIN keep the queue open ? Is there any parameter to control this. Since this is a cluster queue, I think the open was done by the cluster reciever channel. |
|
| Back to top |
|
 |
| fjb_saper |
| Posted: Wed Sep 15, 2010 11:57 am Post subject: |
|
|
Grand High Poobah
Joined: 18 Nov 2003
Posts: 20756
Location: LI,NY
|
Set the queue put inhibited.
Check which sender has the queue open. You can then stop the sender channel with mode(inactive). This should minimize the hit to other applications and at the same time release the hold on the queue.
Usually we would suspend the target qmgr then issue the stop channel mode(inactive) on the source qmgr. We did this to allow a clear of certain cluster queues. We would then resume the target qmgr.
Have fun 
_________________
MQ & Broker admin |
|
| Back to top |
|
|
| bruce2359 |
| Posted: Wed Sep 15, 2010 1:16 pm Post subject: |
|
|
Poobah
Joined: 05 Jan 2008
Posts: 9469
Location: US: west coast, almost. Otherwise, enroute.
|
What have you set the HBINT value for the CLUSRCVR channel?
What have you set for DISCINT value for the CLUSRCVR channel?
Disconnect will cause the CLUSRCVR channel to close queue it has open.
_________________
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 |
|
|
| KIT_INC |
| Posted: Thu Sep 16, 2010 7:58 am Post subject: |
|
|
Knight
Joined: 25 Aug 2006
Posts: 589
|
Almost all parameters are default. So the HBINT is 300 and the DISC interval is 6000. This is a busy production system. I have never seen the cluster channel go inactive during the day. I did noticed the cluster local queue open count dropp to zero. But I am not sure under what circumstances. If I have to wait until the channel disconnect before the output count is dropped, there is no way that we can put the change in in the short window. That's why I was wondering if there is some kind of internal control used by the CHIN to release the queue ?
If I understand the manual correctly, HB will only flow when there is no message on the XMITQ. Since this is the cluster XMITQ in a busy production system, I have no way to tell when there will be no message. |
|
| Back to top |
|
|
| fjb_saper |
| Posted: Thu Sep 16, 2010 8:18 am Post subject: |
|
|
Grand High Poobah
Joined: 18 Nov 2003
Posts: 20756
Location: LI,NY
|
In order to change the SCTQ you will have to take the qmgr out of the cluster and stop all running cluster sender channels. And then the queue might still not be empty. Just suspending the qmgr from the cluster does not guarantee you that nobody uses the qmgr to get to another qmgr in the cluster hence you'd have activity on the SCTQ.
Have fun
_________________
MQ & Broker admin |
|
| Back to top |
|
|
| PeterPotkay |
| Posted: Thu Sep 16, 2010 10:44 am Post subject: |
|
|
Poobah
Joined: 15 May 2001
Posts: 7722
|
FJ,
I think the queue he wants to change is a destination queue being put to, not the SCTQ being pulled from.
KIT_INC,
Why do you need to delete and redefine the queue? Why can't you just alter it?
_________________
Peter Potkay
Keep Calm and MQ On |
|
| Back to top |
|
|
| bruce2359 |
| Posted: Thu Sep 16, 2010 11:10 am Post subject: |
|
|
Poobah
Joined: 05 Jan 2008
Posts: 9469
Location: US: west coast, almost. Otherwise, enroute.
|
And: Is this a one-time event? Or will you need to delete and redefine the queue more frequently? If so, will you need to do this on a regular basis?
As Mr. Potkay asks, why do you need to delete and redefine the queue?
_________________
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: Thu Sep 16, 2010 1:10 pm Post subject: |
|
|
Grand High Poobah
Joined: 18 Nov 2003
Posts: 20756
Location: LI,NY
|
| bruce2359 wrote: |
And: Is this a one-time event? Or will you need to delete and redefine the queue more frequently? If so, will you need to do this on a regular basis?
As Mr. Potkay asks, why do you need to delete and redefine the queue? |
Maybe change of queue type (local to alias)?
_________________
MQ & Broker admin |
|
| Back to top |
|
|
| bruce2359 |
| Posted: Thu Sep 16, 2010 1:17 pm Post subject: |
|
|
Poobah
Joined: 05 Jan 2008
Posts: 9469
Location: US: west coast, almost. Otherwise, enroute.
|
I seem to recall that put-inhibiting the cluster queue (or taking it out of the cluster) will result in the queue being closed by the MCA.
_________________
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: Thu Sep 16, 2010 1:23 pm Post subject: |
|
|
Grand High Poobah
Joined: 18 Nov 2003
Posts: 20756
Location: LI,NY
|
| bruce2359 wrote: |
| I seem to recall that put-inhibiting the cluster queue (or taking it out of the cluster) will result in the queue being closed by the MCA. |
Immediately or eventually? We noticed that even though the algorithm was no longer putting to the queue (qmgr suspended) the channel kept the queue open.
A stop chl mode(inactive) on the sender qmgr then immediately droped the handle on the queue as when the channel restarted there was nothing to put to the queue (qmgr suspended but still participating in some request / reply scenarios not involving said queue).
A script in MO72 allowed us to do this quick and painless.
Have fun
_________________
MQ & Broker admin |
|
| Back to top |
|
|
| bruce2359 |
| Posted: Thu Sep 16, 2010 2:00 pm Post subject: |
|
|
Poobah
Joined: 05 Jan 2008
Posts: 9469
Location: US: west coast, almost. Otherwise, enroute.
|
| Quote: |
| Immediately or eventually? |
Well, yes.
That's why I suggested put-inhibiting the cluster queue or taking it out of the cluster. Either causes the clustering software to notify the repositories that this object is no longer available; and should cause the CLUSRCVR to release its open handle.
Setting heartbeat/disconnect interval to low(er) values would accomplish the same thing - presuming that there are idle periods within these values that would allow the receiving end to go inactive.
| Quote: |
| We noticed that even though the algorithm was no longer putting to the queue (qmgr suspended) the channel kept the queue open. |
Not a surprise, as suspend merely notifies other qmgrs not to use the suspended qmgr as a destination for any new queue binds.
Still waiting for the OP to respond to why this necessary...
_________________
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 |
|
|
| KIT_INC |
| Posted: Thu Sep 23, 2010 9:40 am Post subject: |
|
|
Knight
Joined: 25 Aug 2006
Posts: 589
|
| Sorry, that I did not repsonse for a while. This is a one time change and we have decided to move it to another longer maintenance window instead of taking the chance of not able to perform the change and got nailed as a change failure. Thanks for all the good input. When I have a chance I'll try all the suggestions in a test environment. |
|
| Back to top |
|
|
| PeterPotkay |
| Posted: Thu Sep 23, 2010 4:14 pm Post subject: |
|
|
Poobah
Joined: 15 May 2001
Posts: 7722
|
| PeterPotkay wrote: |
FJ,
KIT_INC,
Why do you need to delete and redefine the queue? Why can't you just alter it? |
_________________
Peter Potkay
Keep Calm and MQ On |
|
| Back to top |
|
|
| fjb_saper |
| Posted: Thu Sep 23, 2010 7:34 pm Post subject: |
|
|
Grand High Poobah
Joined: 18 Nov 2003
Posts: 20756
Location: LI,NY
|
| PeterPotkay wrote: |
| PeterPotkay wrote: |
FJ,
KIT_INC,
Why do you need to delete and redefine the queue? Why can't you just alter it? |
|
AFAIK you can't alter the queue type. Remote to local or vice versa for example.
_________________
MQ & Broker admin |
|
| Back to top |
|
|
| bruce2359 |
| Posted: Thu Sep 23, 2010 7:49 pm Post subject: |
|
|
Poobah
Joined: 05 Jan 2008
Posts: 9469
Location: US: west coast, almost. Otherwise, enroute.
|
Nope, you can't alter the object type; but you can alter attributes that cause the object to be removed from the clustering algorithm.
_________________
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 |
|
|
|
|
