amqrmppa chewing up CPU

Discussion:

Potkay, Peter M (ISD, IT)

2005-10-12 18:43:17 UTC

Got 1 amqrmppa exe using 50 % CPU. MQ 5.3.0.8 on Windows 2000 SP4. Got the PID, and using MO71 I did a wildcard Queue Usage command to see which queues and channels were using this PID. A lot of them, more than 64, which I find odd, since I thought amqrmppa would spawn a max of 64 threads.

Anyway, any safe way of stopping this exe from using this CPU short of bouncing the QM?

Peter Potkay
ISD MQSeries Support Manager
The Hartford Financial Services
x77906
IBM MQSeries Certified

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Paul Clarke

2005-10-12 19:02:34 UTC

Permalink

Peter,

Before you start killing things why not take a brief trace and work out
what it is doing. Is it possible it's really doing lots of stuff for valid
reasons ?. From a DIS CHS(*) command you can determine which channels are
running in this AMQRMPPA process. By looking at the channel status output
you can see whether one (or more) of them are sending a lot of messages.
You might also see it from looking at your transmission queues. RESET
QSTATS(*) etc to see how many messages are being put/got in a time
interval. You might then be able to narrow it down to which application is
using the transmission queue (or am I thinking V 6.0 here ?),

However, an AMQRMPPA will normally process up to 64 channels untill you
have 100*64 channels running at which point each AMQRMPPA will get loaded
up to 100 channels. However, each AMQRMPPA may have many more than 64
queues open right ?

Cheers,
P.

Paul G Clarke
WebSphere Messaging Clients
IBM Hursley

Post by Potkay, Peter M (ISD, IT)
Got 1 amqrmppa exe using 50 % CPU. MQ 5.3.0.8 on Windows 2000 SP4.
Got the PID, and using MO71 I did a wildcard Queue Usage command to
see which queues and channels were using this PID. A lot of them,
more than 64, which I find odd, since I thought amqrmppa would spawn
a max of 64 threads.
Anyway, any safe way of stopping this exe from using this CPU short of bouncing the QM?
Peter Potkay
ISD MQSeries Support Manager
The Hartford Financial Services
x77906
IBM MQSeries Certified
*************************************************************************
This communication, including attachments, is
for the exclusive use of addressee and may contain proprietary,
confidential and/or privileged information. If you are not the intended
recipient, any use, copying, disclosure, dissemination or distribution is
strictly prohibited. If you are not the intended recipient, please notify
the sender immediately by return e-mail, delete this communication and
destroy all copies.
*************************************************************************
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Post by Potkay, Peter M (ISD, IT)
Archive: http://listserv.meduniwien.ac.at/archives/mqser-l.html

Potkay, Peter M (ISD, IT)

2005-10-12 19:59:08 UTC

Permalink

Paul, this is a client concentrator. I have 327 queues on it, and 417 Active channels, mostly SVRCONNs. There is only 1 XMITQ leaving this box, it is quiet.

Most queues are empty when I look at them all in MO71, and the ones with depth are not open (exception / fail type queues).

But it is certainly possible one queue is open for input and output, and a client is spinning on a message so the depth shows zero. How would I find that? Queue Statistics for 327 queues is tedious.

Should I trace and send to IBM?

-Peter

-----Original Message-----
From: MQSeries List [mailto:MQSERIES-0lvw86wZMd9k/bWDasg6f+***@public.gmane.org]
Sent: Wednesday, October 12, 2005 3:03 PM
To: MQSERIES-0lvw86wZMd9k/bWDasg6f+***@public.gmane.org
Subject: Re: amqrmppa chewing up CPU

Peter,

Before you start killing things why not take a brief trace and work out
what it is doing. Is it possible it's really doing lots of stuff for valid
reasons ?. From a DIS CHS(*) command you can determine which channels are
running in this AMQRMPPA process. By looking at the channel status output
you can see whether one (or more) of them are sending a lot of messages.
You might also see it from looking at your transmission queues. RESET
QSTATS(*) etc to see how many messages are being put/got in a time
interval. You might then be able to narrow it down to which application is
using the transmission queue (or am I thinking V 6.0 here ?),

However, an AMQRMPPA will normally process up to 64 channels untill you
have 100*64 channels running at which point each AMQRMPPA will get loaded
up to 100 channels. However, each AMQRMPPA may have many more than 64
queues open right ?

Cheers,
P.

Paul G Clarke
WebSphere Messaging Clients
IBM Hursley

Post by Potkay, Peter M (ISD, IT)
Got 1 amqrmppa exe using 50 % CPU. MQ 5.3.0.8 on Windows 2000 SP4.
Got the PID, and using MO71 I did a wildcard Queue Usage command to
see which queues and channels were using this PID. A lot of them,
more than 64, which I find odd, since I thought amqrmppa would spawn
a max of 64 threads.
Anyway, any safe way of stopping this exe from using this CPU short
of bouncing the QM?
Peter Potkay
ISD MQSeries Support Manager
The Hartford Financial Services
x77906
IBM MQSeries Certified
*************************************************************************
This communication, including attachments, is
for the exclusive use of addressee and may contain proprietary,
confidential and/or privileged information. If you are not the intended
recipient, any use, copying, disclosure, dissemination or distribution is
strictly prohibited. If you are not the intended recipient, please notify
the sender immediately by return e-mail, delete this communication and
destroy all copies.
*************************************************************************
Instructions for managing your mailing list subscription are
provided in the Listserv General Users Guide available at

http://www.lsoft.com

Post by Potkay, Peter M (ISD, IT)
Archive: http://listserv.meduniwien.ac.at/archives/mqser-l.html

Paul Clarke

2005-10-12 20:47:27 UTC

Permalink

Peter,

I don't understand why you say "Queue Statistics for 327 queues is
tedious". Can't you just do a RESET QSTATS(*) in MO71 and sort by enqueue.?
If you have 417 SVRCONNs it seems most likely that one (or more) of your
clients is either doing some serious messaging or spinning like doing an
MQGET(NO WAIT). I would do a DIS CHS(*) and look at the number of bytes
sent/received and last message time etc to determine whether you have a
rogue client. You would be able to see the IP address etc, possibly issue a
STOP CHANNEL(). If this were MQ V6 you could see the name of the
application as well.

I was suggesting you take a trace and look at yourself but you are, of
course, at liberty to send it to IBM. Send it to me if you like :-) There
is a good chance the trace file would be fairly easy to read if the
activity is as high as you say. The trace will show which MQI calls are
being issued and with which options. However, we have not designed the
trace to be only used by IBM personnel - we don't try and hide anything.
For many problems any relatively technically savvy person should be able to
understand what's going on.

Cheers,
P.

Paul G Clarke
WebSphere Messaging Clients
IBM Hursley

Post by Potkay, Peter M (ISD, IT)
Paul, this is a client concentrator. I have 327 queues on it, and
417 Active channels, mostly SVRCONNs. There is only 1 XMITQ leaving
this box, it is quiet.
Most queues are empty when I look at them all in MO71, and the ones
with depth are not open (exception / fail type queues).
But it is certainly possible one queue is open for input and output,
and a client is spinning on a message so the depth shows zero. How
would I find that? Queue Statistics for 327 queues is tedious.
Should I trace and send to IBM?
-Peter
-----Original Message-----
Sent: Wednesday, October 12, 2005 3:03 PM
Subject: Re: amqrmppa chewing up CPU
Peter,
Before you start killing things why not take a brief trace and work out
what it is doing. Is it possible it's really doing lots of stuff for valid
reasons ?. From a DIS CHS(*) command you can determine which channels are
running in this AMQRMPPA process. By looking at the channel status output
you can see whether one (or more) of them are sending a lot of messages.
You might also see it from looking at your transmission queues. RESET
QSTATS(*) etc to see how many messages are being put/got in a time
interval. You might then be able to narrow it down to which application is
using the transmission queue (or am I thinking V 6.0 here ?),
However, an AMQRMPPA will normally process up to 64 channels untill you
have 100*64 channels running at which point each AMQRMPPA will get loaded
up to 100 channels. However, each AMQRMPPA may have many more than 64
queues open right ?
Cheers,
P.
Paul G Clarke
WebSphere Messaging Clients
IBM Hursley

*************************************************************************