General performance principles should be the same between Qlik Sense and QlikView, however the tool set for Qlik Sense needs to be developed more, I admit.
There is a performance scalability tool that's available from Qlik, but that's about it...
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I have been working on the Sense server for nearly 8 months now and never faced any issues with it.
In order to make use you are following all the best practices I would suggest you to go through this document: