Regularly on large scale citrix implementations the citrix license server might suffer due to the number of requests it’ll receive at peak times. One tip I did come across recently was to review your thread count on the server. This would take 2 forms, one web server thread count and the other server. Defaults for these are normally quite conservative and generally if you are running in a virtual environment you can afford yourself the opportunity to increase these.
Enclosed are the details on how: