I have an SSAS server that experiences massive memory usage when I connect PBI desktop to it to try to publish a report. I don't experience this issue with our clunky, old, on-premise server. I am using the same gateway to access both servers. Why would the beefier Prod server have memory issues only when interrrogating using PBI? When I emulate the query using the SQL browser, I don;t get the memory drain problem.
You said " I am using the same gateway to access both servers. ", so you are connecting to ssas in import mode, right? Power bi has some limitation about your data size, you can refer to this answer: https://www.quora.com/Can-I-import-a-10-GB-data-set-into-Power-BI.
I don't think there is any limitation whatsoever since I am reading the data directly from an SSAS dtabase in real-time, NOT importing the data. Besides, the entire cube is tiny, less than 1 GB.