WF workflow for a web user across a server farm?
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We would like to use Windows Workflow to guide our web users down a navigational path.

We have a server farm, so this translates to a long-running workflow for each user; which multiple servers must be aware of.

What we've prototyped so far is the use of WorkflowApplication and the SQL Persistence Provider. This works, but we're concerned about all of the SQL Server activity and its performance.

We found that someone has created an AppFabric Cache persistence provider ([blog post here][1]), which appeals to us because it means hydrating our workflows to RAM instead of SQL; but they clearly state that it's not been production-tested.

Any advice, thoughts, or suggestions?

  [1]: http://blogical.se/blogs/mikael/archive/2011/02/01/using-appfabric-cache-as-wf-persistence-store.aspx