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| unclehunty |
 Posted: Wed Jun 10, 2009 3:40 am Post subject: Reducing the on disk size of the 'q' file |
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Newbie
Joined: 10 Jun 2009
Posts: 7
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Chaps,
I have come across a small problem in the last day or two. I have a MQ5.3 running on W2K3 plus Patrol for monitoring.
We had 30k messages come through to be picked up by a very slow application at about 1000 per hour. The q file on the disk went up to the limit of the disk space on that drive and has been sitting there for hours without reducing. I have stopped the sender channel and had the application stop taking messages off the queue via their svrconn. No handles are on the queue and there is nothing else visibly maintaining a connection to this queue.
The problem is that the 'q' file on the disk will not reduce so I need some help and advice on how it all works, especially in light of the very small amount of space left on the disk.
- can anyone point me to some reading material that explains(or tell me) under what circumstances this file reduces in size.
- can anyone recommend a way to force the file size to reduce, there are other messages that need to go on this server that are unrelated to the offending application and rightly they are complaining that the badly written and barely supported app is farnarkling the server.
- I am reluctant to restart the server during the business day and am not even sure that will work, maybe someone can tell me if it should
hunty |
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| exerk |
| Posted: Wed Jun 10, 2009 3:49 am Post subject: |
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Jedi Council
Joined: 02 Nov 2006
Posts: 6339
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If you do a search within the forums you should find some recent discussion on how, and when, a queue manager 'recovers' disk space by compacting a queue file...brave man to still be on V5.3 
_________________
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. |
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| Vitor |
| Posted: Wed Jun 10, 2009 3:51 am Post subject: Re: Reducing the on disk size of the 'q' file |
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Grand High Poobah
Joined: 11 Nov 2005
Posts: 26093
Location: Texas, USA
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| unclehunty wrote: |
| - can anyone point me to some reading material that explains(or tell me) under what circumstances this file reduces in size. |
AFAIK the queue file is compressed by the queue manager automatically when it's not busy. I don't know if this behaviour is documented.
| unclehunty wrote: |
| - can anyone recommend a way to force the file size to reduce, there are other messages that need to go on this server that are unrelated to the offending application and rightly they are complaining that the badly written and barely supported app is farnarkling the server. |
Bounce the queue manger. AFAIK there's no "compress queue" command. The other trick is to restart the slow application. As the queue depth reduces, the queue manager is more likely to realise there's space to be reclaimed.
| unclehunty wrote: |
| - I am reluctant to restart the server during the business day and am not even sure that will work, maybe someone can tell me if it should |
It should. Schedule some after hours maintenance.
You don't mention what version of v5.3 you're using. Later versions of v5.3 (which you should be using) were better at housekeeping than earlier ones. The v6 version (which you should be planning to upgrade to asap) is very good at this.
_________________
Honesty is the best policy.
Insanity is the best defence. |
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| PeterPotkay |
| Posted: Wed Jun 10, 2009 4:05 am Post subject: |
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Poobah
Joined: 15 May 2001
Posts: 7722
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My tests have shown that issuing the clear queue command would cause the QM to shrink a huge q file. There must be at least one message on the queue for this trick to work. Do a search here for that thread for more details. Its not documented in the manuals, but has worked repeatedly for me in the past.
_________________
Peter Potkay
Keep Calm and MQ On |
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| unclehunty |
| Posted: Wed Jun 10, 2009 4:35 am Post subject: |
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Newbie
Joined: 10 Jun 2009
Posts: 7
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Peter - The clear queue idea is good, however I still have 22k messages on the queue and want to keep them. I was looking more for a way to shrink the size down while the messages remain.
Vitor - I have had the slow application stopped for about 20 minutes and left it to be idle for a while, neither had the desired effect. And don't get me started on running 5.3. We still have some 5.2 servers running on WinNT.
I will suggest that a server restart is scheduled for tonight. I have also set the max messages down so that we don't get this again and the messages back up on the xmit queue on the sending server which has literally hundreds of bytes of storage. |
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| Vitor |
| Posted: Wed Jun 10, 2009 5:01 am Post subject: |
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Grand High Poobah
Joined: 11 Nov 2005
Posts: 26093
Location: Texas, USA
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| unclehunty wrote: |
| Vitor - I have had the slow application stopped for about 20 minutes and left it to be idle for a while, neither had the desired effect. And don't get me started on running 5.3. We still have some 5.2 servers running on WinNT. |
So getting the application fixed is probably out of the question then?
_________________
Honesty is the best policy.
Insanity is the best defence. |
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| exerk |
| Posted: Wed Jun 10, 2009 5:03 am Post subject: |
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Jedi Council
Joined: 02 Nov 2006
Posts: 6339
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| Vitor wrote: |
| unclehunty wrote: |
| Vitor - I have had the slow application stopped for about 20 minutes and left it to be idle for a while, neither had the desired effect. And don't get me started on running 5.3. We still have some 5.2 servers running on WinNT. |
So getting the application fixed is probably out of the question then? |
Surely you are forgetting the MQ Mantra: 'it's always our fault!'
_________________
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. |
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| unclehunty |
| Posted: Wed Jun 10, 2009 7:02 am Post subject: |
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Newbie
Joined: 10 Jun 2009
Posts: 7
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At 0720 this morning we got the sky is falling, teen pregnancies are rising and vigilant zombies are attacking children because of MQ.
This afternoon they decided that some work need to be done on the app working faster and selecting what information is actually needed.
Hooray for being too late.
I used to work as a Notes/Domino admin, I have had years of that mantra. Everyone knows it's the Windows admins that are to blame. |
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| Vitor |
| Posted: Wed Jun 10, 2009 7:13 am Post subject: |
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Grand High Poobah
Joined: 11 Nov 2005
Posts: 26093
Location: Texas, USA
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| unclehunty wrote: |
| Everyone knows it's the Windows admins that are to blame. |
Welcome to the forum, can I get you a chair & perhaps a cool drink?
_________________
Honesty is the best policy.
Insanity is the best defence. |
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| exerk |
| Posted: Wed Jun 10, 2009 11:48 am Post subject: |
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Jedi Council
Joined: 02 Nov 2006
Posts: 6339
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| unclehunty wrote: |
| ...teen pregnancies are rising... |
Please tell me you're NOT responsible
As for the zombies, sorry, but Vitor keeps me very busy in the dungeon...
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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. |
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