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Increase of Stack size impact

 
Agur Dunit
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Hi there,

Please, what is the impact of increasing the Stack size with the -Xss option for the whole system. is there any relationship or formula between -Xms, -Xmx and -Xss options.
Is it necessary to increase the -Xmx option When i increase the -Xss option.

I'm using Weblogic 9.1 within a machine of 16GB under AIX 64bits and IBM JVM. My parameters are : -Xms=-Xmx=1GB and i think pass the -Xss to 1MB because i get many StackOverflow exceptions.

Think you for your help
 
Marcos Maia
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How many maximum concurrent threads does your server gets? I've seen applications that require 2048k for each thread(-Xss) and worked fine. It all depends on how many concurrent users you have. Just have to remember that you're allocating 1024k for each thread in the server.
You may have to increase Xmx if you have too many concurrent users, but memory is cheap these days anyway!!!

regards,
Marcos Maia.
 
Agur Dunit
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Hi Marcos, Think you very much for the response.

In the production environment we have 60 Threads and 300 oracle processes. RAM Memory usage is under 6GB.
Number of processes in the Weblogic run queue can achieve 20. We can acheive 10 transaction/seconde.

Best regards
 
Marcos Maia
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Agur Dunit wrote:Hi Marcos, Think you very much for the response.

In the production environment we have 60 Threads and 300 oracle processes. RAM Memory usage is under 6GB.
Number of processes in the Weblogic run queue can achieve 20. We can acheive 10 transaction/seconde.

Best regards


One easy thing to check is if your environment is respecting the recommended memory usage for the system on the -Xmx table in jrockit documentation:

http://download.oracle.com/docs/cd/E13150_01/jrockit_jvm/jrockit/jrdocs/refman/optionX.html#wp999528

You're memory usage should respect the recommended values if you want better overall performance. Also if you have other services in the same machine this usually affects performance and you should make a fine tunning of overall environment using monitoring tools, tunning the O.S, etc.

regards.
 
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