Hi Pavel, Rob and Peter,
thanks for the insight. I did insisted it must be some code not closing
connection under certain circumstances, and ran a trace and sent to IBM for
analysis. But were told all connections were closed properly, which
virtually nullified my insertion to the developers. I'll following your
advice to do more research.
There seem to be no tcp_keepcnt on AIX, a command "no -otcp_keepcnt"
returned my the following "0821-057 no: The ioctl SIOCGNETOPT system call
failed.".
again, many thanks. Maybe see you in Las Vegas?
Ben
Pavel Tolkachev
<pavel.tolkachev To: [EMAIL PROTECTED]
@DB.COM> cc:
Sent by: Subject: Re: many svrconn instances, as
many amqcrsta running
MQSeries List
<[EMAIL PROTECTED]
en.AC.AT>
06/08/2004 12:51
PM
Please respond
to MQSeries List
Hello Benjamin,
T.Rob is right in principle, of course. But I guess, the connections had to
go down, anyway, with these tcp settings. Just in case, what was your
tcp_keepcnt? And, did you check your new tcp parameters took effect
immediately? Also, I am not sure if the change takes effect for the
existing connections (never checked that..). What else may have happened is
that the applications were actually alive, although idle, in which case you
do not have much control.. that's why DoS attacks are so nasty when done by
the legitimate apps :-)
Pavel
"Wyatt, T. Rob"
<[EMAIL PROTECTED] To:
[EMAIL PROTECTED]
MERICA.COM> cc:
Sent by: MQSeries Subject: Re: many
svrconn instances, as many amqcrsta running
List
<[EMAIL PROTECTED]
C.AT>
06/08/2004 11:05 AM
Please respond to
MQSeries List
Benjamin,
Using QMgr tuning to bring these channels down addresses only the symptom.
Unless you correct the problem at it's root, nothing you do will scale
well.
The application MUST properly close it's resources and disconnect from the
QMgr. If you successfully tune the channels, you will probably get through
development and testing but you might not see the real impact until the
application is in Production. On the other hand, if you leave your
channels
as they are now, you will have a convenient way to measure the success of
the developers in fixing their code.
-- T.Rob
-----Original Message-----
From: MQSeries List [mailto:[EMAIL PROTECTED] Behalf Of
Benjamin F. Zhou
Sent: Tuesday, June 08, 2004 10:52 AM
To: [EMAIL PROTECTED]
Subject: many svrconn instances, as many amqcrsta running
Hi,
AIX, 5.1, MQ5.3, csd06: we have JMS clients connecting to MQ via client
mode. Initially, the maxchannels got reached quickly, and application
failed at pretty low stress level. After I raised both MaxChannels and
MaxActiveChannels to 400, the test went through pretty well.
However, after each test, I see large number of the svrconn channel and the
same number of amqcrsta running against the same qmgr. There's no sign they
will ever come down, although I set keepAlive=yes and tcp_keepintvl and
tcp_keepidle to 10 seconds.
What else can be done to bring down these orphaned processes?
I saw many postings concerning this or similar problem at mqseries.net ,
just none has found a solution.
Anyone has more idea on this?
best regards,
Benjamin Zhou
Mercedes-Benz USA.
x2474
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