XenDesktop 5 Scalability
DJFeller wrote an excellent article on XenDesktop scalability and especially on Xendeskop Controller capacity:
Think about the architecture of XenDesktop 5. One of the core components responsible for an acceptable user experience during the initial authentication and launch of the virtual desktop are the controllers. If these controllers get overloaded, it will take users longer to launch their virtual desktops. What is acceptable is based on the users and their requirements. But for this example let’s say when we hit the icon for the virtual desktop we expect a response within 2 seconds. How many controllers do I need for 5,000, 10,000, 15,000 or even 20,000 users? It really boils down to the logon storm and the controller hardware. The more powerful your hardware is; the greater of a storm a single controller can tolerate.
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