Greg Galloway just released a new version of the Analysis Services Stored Procedure Project that includes a command to clear the File System Cache, including the standby cache.

A technical discussion about how it works is available in this post on his blog.

It is a great tool to have whenever you need to do performance measures with a real cold cache.
Kudos to Greg for his efforts! 

Originally appeared on: http://sqlblog.com/blogs/marco_russo/archive/2010/12/30/clearing-standby-cache-and-other-caches-in-analysis-services.aspx