Final release - patterns & practices Performance Testing Guidance for Web Applications. It is the approach. I used its Chapter 9 – Determining Performance Testing Objectives to create Performance Testing Objectives Document Template. It definitely helped to achieve results while conducting Performance Workshop In Munich MTC Labs.
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My favorite page is this http://www.codeplex.com/PerfTesting/Wiki/View.aspx?title=How%20Tos&referringTitle=Home