Restricting Thread Pool for Servlet instances

I am using WebLogic5.1.0 version wherein I am registering a Servlet which
would be called by all the clients connecting
to my aplication. The servlet's service methods is taking some time to
execute. Since the servlet is following a SingleThreadModel, when there are
a large number of Clients connected, the number instances of Servlets
created are very high and the number of thread in the Application Server
process becomes very high affecting the performance of the other
applications.
Is it possible to restrict the number of instances of the servlets that get
created in the Application server ?
What are the setting required to achieve this ?
Sandeep

Hi.
I'm not aware of a property setting that allows you to restrict the number of
servlet instances in WLS for the SingleThreadModel. The number of execute
threads is fixed - it does not grow depending on load. You can set this value
in the weblogic.properties file by setting weblogic.system.executeThreadCount.
This value is 15 by default.
It does sound like you are reaching the max capability of your
server/hardware. You should try tuning WLS.
Here are a couple of suggestions:
1. Try adjusting the executeThreadCount value to a higher value. Start by
setting it to 30 - see if that makes any difference.
2. Check out the following tuning guide:
http://www.weblogic.com/docs51/admindocs/tuning.html
3. Here is a list of admin properties that might aid in tuning:
http://www.weblogic.com/docs51/adminhelp/AdminPropertyHelp.html
4. If you are still having problems you might do better by posting this issue
to the performance newsgroup.
Regards,
Michael
Sandeep Rajpathak wrote:
I am using WebLogic5.1.0 version wherein I am registering a Servlet which
would be called by all the clients connecting
to my aplication. The servlet's service methods is taking some time to
execute. Since the servlet is following a SingleThreadModel, when there are
a large number of Clients connected, the number instances of Servlets
created are very high and the number of thread in the Application Server
process becomes very high affecting the performance of the other
applications.
Is it possible to restrict the number of instances of the servlets that get
created in the Application server ?
What are the setting required to achieve this ?
Sandeep--
Michael Young
Developer Relations Engineer
BEA Support

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"Ethan Allen" <[email protected]> wrote in message
news:3e0220a1$[email protected]..
Thanks, Dimitri and Slava !
I will do this and learn a little emore ...FYI, there is a web site dedicated to weblogic documentation -
http://e-docs.bea.com/
Pick your server version, go to "Search", type "thread dump".
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Slava Imeshev
>
ethan
"Slava Imeshev" <[email protected]> wrote:
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For windows press <Ctrl>+<Break> in the server shell window,
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Regards,
Slava Imeshev
"Ethan Allen" <[email protected]> wrote in message
news:3e020fb4$[email protected]..
Thanks for your reply, Dimitri.
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"Dimitri I. Rakitine" <[email protected]> wrote:
Did you try looking at thread dumps when this happens ?
Ethan Allen <[email protected]> wrote:
We've set up thread pools for several execute queues dedicated to
high-load
servlets
in our application. Once in a while, we get into a condition in
which
none of
these threads are available and then the threads never become
available
- we have
to restart the server.
I realize that this is a pretty generic description of the problem:-) but I wonder
if anyone else has encountered this and has an idea what might be
causing
it ?
Right now I am guessing that something in our code causes a
resource
contention
that eventually deadlocks all the threads. But that is just a
guess.
>>>>
Dimitri

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Author: [email protected]
Date: 2008-05-07 14:24:53 -0700 (Wed, 07 May 2008)
Log Message:
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QA: Yes - Jorge verified in the QE lab
Doc: No
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Boy am I just flooded with just 6.1 migration issues. Life was much
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Looking at Config.Dtd I couldnt see the different thread pools that WLS
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a) Servlets
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Aswin Dinakar wrote:
Boy am I just flooded with just 6.1 migration issues. Life was much
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Looking at Config.Dtd I couldnt see the different thread pools that WLS
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b) RMI
c) JMS
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jms thread pool.

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Ethan,
"Ethan Allen" <[email protected]> wrote in message
news:3e0220a1$[email protected]..
Thanks, Dimitri and Slava !
I will do this and learn a little emore ...FYI, there is a web site dedicated to weblogic documentation -
http://e-docs.bea.com/
Pick your server version, go to "Search", type "thread dump".
Regards,
Slava Imeshev
>
ethan
"Slava Imeshev" <[email protected]> wrote:
Hi Ethan,
For windows press <Ctrl>+<Break> in the server shell window,
for *nix send kill -3 {server PID}.
Regards,
Slava Imeshev
"Ethan Allen" <[email protected]> wrote in message
news:3e020fb4$[email protected]..
Thanks for your reply, Dimitri.
We have not looked at thread dumps. How may we do this ?
Ethan
"Dimitri I. Rakitine" <[email protected]> wrote:
Did you try looking at thread dumps when this happens ?
Ethan Allen <[email protected]> wrote:
We've set up thread pools for several execute queues dedicated to
high-load
servlets
in our application. Once in a while, we get into a condition in
which
none of
these threads are available and then the threads never become
available
- we have
to restart the server.
I realize that this is a pretty generic description of the problem:-) but I wonder
if anyone else has encountered this and has an idea what might be
causing
it ?
Right now I am guessing that something in our code causes a
resource
contention
that eventually deadlocks all the threads. But that is just a
guess.
>>>>
Dimitri

Restricting Thread Pool for Servlet instances

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