Hi, 

We are currently investigating some performance issues for a client, and it seems like the issues only appears once one or more A/B tests are running on the site.

When we set up A/B tests we get a lot of the following exceptions in the log files:

System.InvalidOperationException: ValueFactory attempted to access the Value property of this instance.
   at System.Lazy`1.CreateValue()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Lazy`1.get_Value()
   at EPiServer.Marketing.Testing.Web.TestHandler.EvaluateKpis(Object sender, EventArgs e)

This is happning even though we are using EPI server 11.

In sum this leads me to believe that there are some performance challenges with the EPiServer A/B testing module. 

Has anyone else seen this?