PBI Refresh Fails - with error Data source error:The XML for Analysis request timed

HI Anonymous ,

There could be a few reasons:

You may have exceeded the capacity limit, or the node level limit.  You might have too many reports refreshing simultaneously.  You may need to increase the timeout.  Your data source itself might not be feeding your query fast enough.

Once you check all of those things out you can start the more painful (in my mind) work of breaking up your queries into smaller chunks and run them separately.  Or, you could implement incremental refresh and do that from the beginning with partitions.