It is really hard to say how much memory does the Admin panel take, because the report is for the entire application. The amount of memory is a function from your online visitors, server configuration and page content.
I want to assure you that we are working on performance optimizations in the admin part. What you could do in the meantime is to disable the dashboard (or turn some of its features off).
We apologize that we could not help you much, but we believe that we will be able to provide a solution soon.
All the best,
the Telerik team
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