| Author |
Message
|
| lash |
 Posted: Fri Mar 05, 2010 7:59 am Post subject: Active Logs filling |
 |
|
Apprentice
Joined: 14 May 2003
Posts: 47
|
Hello All,
Iam trying to fill the active logs for testing the qmgr behaviour. I filled all the queues with persistant msgs, but active logs are not filling up. Can anyone suggest how i can test this scenario.
only one channel is running and putting the msgs.
Below are my thoughts.
1=if i put msgs with msg length atleast more than 3kb and get msgs at same time, active logs will fill ? how many channels should matter ?
2=if i run multiple channels sending and receiving msgs from queues active log will fill ? does the size of msg matter here ? how many channels should matter ?
3=any other advice from gurus.
AIX, MQ Version 6.
Qmgr behaviour testing
1=After active logs r full and qmgr stops abruptly. will the qmgr starts. If not how to make it start. so that we can make a recovery procedure.
2=if it starts, how long will it take to start. so that we can anticipate the production down time in case of this scenario.
thanks,
lash.
Last edited by lash on Fri Mar 05, 2010 8:13 am; edited 1 time in total |
|
| Back to top |
|
 |
| Vitor |
| Posted: Fri Mar 05, 2010 8:03 am Post subject: Re: Active Logs filling |
|
|
Grand High Poobah
Joined: 11 Nov 2005
Posts: 26093
Location: Texas, USA
|
| lash wrote: |
| Iam trying to fill the active logs for testing the qmgr behaviour. |
Test what behaviour? That it'll stop working when the logs fill?
Trust me, it does. 
_________________
Honesty is the best policy.
Insanity is the best defence. |
|
| Back to top |
|
|
| Vitor |
| Posted: Fri Mar 05, 2010 8:11 am Post subject: Re: Active Logs filling |
|
|
Grand High Poobah
Joined: 11 Nov 2005
Posts: 26093
Location: Texas, USA
|
| lash wrote: |
| 1=if i put msgs with msg length atleast more than 3kb and get msgs at same time, active logs will fill ? |
Probably not
| lash wrote: |
| how many channels should matter ? |
No.
| lash wrote: |
| 2=if i run multiple channels sending and receiving msgs from queues active log will fill ? |
Probably not
| lash wrote: |
| does the size of msg matter here ? |
Yes
| lash wrote: |
| how many channels should matter ? |
No
| lash wrote: |
| 3=any other advice from gurus. |
Tell us what you're trying to test.
_________________
Honesty is the best policy.
Insanity is the best defence. |
|
| Back to top |
|
|
| lash |
| Posted: Fri Mar 05, 2010 8:17 am Post subject: |
|
|
Apprentice
Joined: 14 May 2003
Posts: 47
|
Hi vitor, this is what iam trying to test.
Qmgr behaviour testing
1=After active logs r full and qmgr stops abruptly. will the qmgr starts. If not how to make it start. so that we can make a recovery procedure.
2=if it starts, how long will it take to start. so that we can anticipate the production down time in case of this scenario.
from your reply
does the size of msg matter here ?
Yes
how much size atleast i should start pumping into queues to see active logs filling up. |
|
| Back to top |
|
|
| mvic |
| Posted: Fri Mar 05, 2010 9:00 am Post subject: Re: Active Logs filling |
|
|
Jedi
Joined: 09 Mar 2004
Posts: 2080
|
| lash wrote: |
| Iam trying to fill the active logs for testing the qmgr behaviour. I filled all the queues with persistant msgs, but active logs are not filling up. Can anyone suggest how i can test this scenario. |
If your logs fill, then your apps should get MQRC_BACKED_OUT or MQRC_RESOURCE_PROBLEM reason codes. The queue manager should recover automatically. |
|
| Back to top |
|
|
| Vitor |
| Posted: Fri Mar 05, 2010 9:14 am Post subject: |
|
|
Grand High Poobah
Joined: 11 Nov 2005
Posts: 26093
Location: Texas, USA
|
| lash wrote: |
| 1=After active logs r full and qmgr stops abruptly. will the qmgr starts. |
It stops working, it doesn't stop running.
Whatever's causing the log to fill will probably stop running as the queue manager throws it off. As will most other applications connected to the queue manager at the time.
It is to these your recovery efforts should be focused.
_________________
Honesty is the best policy.
Insanity is the best defence. |
|
| Back to top |
|
|
| fjb_saper |
| Posted: Fri Mar 05, 2010 1:10 pm Post subject: |
|
|
Grand High Poobah
Joined: 18 Nov 2003
Posts: 20756
Location: LI,NY
|
Also the behavior is different with linear logs vs circular logs.
Have fun 
_________________
MQ & Broker admin |
|
| Back to top |
|
|
| bruce2359 |
| Posted: Fri Mar 05, 2010 1:44 pm Post subject: |
|
|
Poobah
Joined: 05 Jan 2008
Posts: 9469
Location: US: west coast, almost. Otherwise, enroute.
|
| Quote: |
| It stops working, it doesn't stop running. |
More accurately, when the logs become full, the next attempt to write something to the log (your app trying to put or get a persistent message, for example) will result in your application being presented with a ReasonCode 2003 (07D3) (RC2003): MQRC_BACKED_OUT
Extracted from the WMQ Messages manual:
Explanation
The current unit of work encountered a fatal error or was backed out. ...
- On an MQGET, MQPUT, or MQPUT1 call that is operating within a unit of
work, when the unit of work has already encountered an error that prevents the unit of work being committed (for example, when the log space is exhausted).
The queue manager continues to operate, but your applications - those participating in a unit of work - will fail until log space is made available.
_________________
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 |
|
|
| mvic |
| Posted: Fri Mar 05, 2010 1:50 pm Post subject: |
|
|
Jedi
Joined: 09 Mar 2004
Posts: 2080
|
| bruce2359 wrote: |
| Quote: |
| It stops working, it doesn't stop running. |
More accurately, when the logs become full, the next attempt to write something to the log (your app trying to put or get a persistent message, for example) will result in your application being presented with a ReasonCode 2003 (07D3) (RC2003): MQRC_BACKED_OUT |
Agree.
You can also get MQRC_RESOURCE_PROBLEM - as I said a few posts back. |
|
| Back to top |
|
|
| bruce2359 |
| Posted: Fri Mar 05, 2010 2:30 pm Post subject: |
|
|
Poobah
Joined: 05 Jan 2008
Posts: 9469
Location: US: west coast, almost. Otherwise, enroute.
|
Refer to (read) the WMQ System Admin Guide.
There is narrative in one section on how to calculate log file size; and another section on how to manage the logs.
_________________
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 |
|
|
| lash |
| Posted: Wed Mar 10, 2010 7:30 am Post subject: |
|
|
Apprentice
Joined: 14 May 2003
Posts: 47
|
Log file never filled,but data file MQHA/data filled up. iam in circular logging in HA Environment. Admin guides etc.. says if long running transactions run, it will fill active logs. check-point, log-head etc..If the primary log files are completely full before the long-running transaction completes, secondary log files are used to avoid the logs getting full.
When the log head is moved and you are using circular logging, the primary log files might become eligible for reuse and the logger, after filling the current file, reuses the first primary file available to it.. bla bla bla.. I read all the docs and no where it clearly states how. Gurus can you advice on how to fill active log, and what should i do to fill the log directory MQHA/log.
truely. |
|
| Back to top |
|
|
| exerk |
| Posted: Wed Mar 10, 2010 7:44 am Post subject: |
|
|
Jedi Council
Joined: 02 Nov 2006
Posts: 6339
|
Start a long running transaction, one that will span the logs...
_________________
It's puzzling, I don't think I've ever seen anything quite like this before...and it's hard to soar like an eagle when you're surrounded by turkeys. |
|
| Back to top |
|
|
| bruce2359 |
| Posted: Wed Mar 10, 2010 7:47 am Post subject: |
|
|
Poobah
Joined: 05 Jan 2008
Posts: 9469
Location: US: west coast, almost. Otherwise, enroute.
|
| Quote: |
| Gurus can you advice on how to fill active log |
Write an application that MQPUTs persistent messages endlessly.
| Quote: |
| and what should i do to fill the log directory MQHA/log. |
Same answer. The log directory is in the filesystem, too.
_________________
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 |
|
|
| lash |
| Posted: Wed Mar 10, 2010 7:52 am Post subject: |
|
|
Apprentice
Joined: 14 May 2003
Posts: 47
|
i wrote a java program which sends persistant msgs continously. but msg size was 3kb only. (it did not filled the log though). to different queues, different depths. i made 10gb of data and 10gb of log. it filled 90% of data and log is same as it was when initailly created 40%.
note: data and log are on saperate file systems. |
|
| Back to top |
|
|
| Vitor |
| Posted: Wed Mar 10, 2010 8:00 am Post subject: |
|
|
Grand High Poobah
Joined: 11 Nov 2005
Posts: 26093
Location: Texas, USA
|
| lash wrote: |
| i wrote a java program which sends persistant msgs continously. but msg size was 3kb only. (it did not filled the log though). to different queues, different depths. i made 10gb of data and 10gb of log. it filled 90% of data and log is same as it was when initailly created 40%. |
I still don't get what you're trying to test. As has been said earlier in this thread, the queue manager won't fail when the log fills; it'll fail your app. This is the same behaviour if your queue manager is under HA as if it isn't.
Assumption: you're trying to test if the queue manager fails over correctly when the log fills.
Answer: It doesn't. See above where I said the queue manager doesn't fail.
(Failover wouldn't help in this situation, as the disc will be equally full on both HA nodes..... )
_________________
Honesty is the best policy.
Insanity is the best defence. |
|
| Back to top |
|
|
|
|
