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Tuning Exchange 2003
For the most part, Exchange 2003 is self-tuning. In Exchange 5.5 and earlier versions, Exchange shipped with a wizard-based tool called the Performance Optimizer. An administrator would launch this tool and answer a series of questions about the server's role, the number and type of users on the server, and what disks were available for use by Exchange. Behind the scenes, the Performance Optimizer would examine available resources and, based on all of this gathered information, it would make some adjustments to the Exchange configuration to tune Exchange properly for each server.
The Performance Optimizer could be used to move databases and transaction log files to different (presumably faster) disks, and it could also be used to limit the amount of memory that the information store (STORE.EXE) could consume. The Performance Optimizer was removed from Exchange starting with Exchange 2000, and it remains missing from Exchange 2003. It was removed because Exchange 2000 (and now Exchange 2003) was made to be self-tuning. If you need to move the databases and transaction logs, that functionality is now found in ESM; however, if you want to limit the amount of memory used by Exchange, you are out of luck—there is no longer any supported way to do this.
http://www.informit.com/articles/article.asp?p=170892&rl=1jeg ser lige om jeg kan finde en beskrivelse på hvordan det gøres i praksis