Load balancing with ABAP based system

Dear Gurus,
I'm newbie on SAP. I searched in SAP library but cannot find exact information.
I was wondering, if a user already logged on a to ABAP based SAP system, how dialog work processes assigned to user?For example, does the user get a work process for each instance or user always remains assigned to the same dialog work process? Or the assignment depends on server load, I mean different dialog work processes of different instances will work for this user?
Any help or URL contains that information will be appreciated.

Hello,
First time logon request :
When a new login request comes, it comes to message server. message server pass this request to best available application server dispatcher.
then dispatcher distributes the requests one after the other to the available work processes. Data is actually processed in the work process, whereby the user who created the request using the SAP GUI is not always assigned the same work
process. There is no fixed assignment of work processes to users.
Once user is already logged in :
Now, new transaction request for already logged on user will be always processed by same application server where he logged in first time. His transaction request from GUI comes to Dispatcher of the application server then dispatcher distributes the requests one after the other to the available free work processes(may be different). (means already logged on user may get different work process but from same application server)
also read this :
http://help.sap.com/saphelp_46c/helpdata/en/fc/eb2e8a358411d1829f0000e829fbfe/content.htm
How dispatcher works
thanks
ashish
Edited by: ashish vikas on Aug 22, 2011 12:06 AM

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Posting
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