We are processing a partition on a cube in latest version of SQL Server 2017 (CU 13, also tried in CU 12 and CU 4) and sometimes it totally freezes. Task manager shows no movement at all - not memory, cpu, nor IO. The only way out is to kill the SSAS process; can't even stop the SSAS service; that is frozen too. We're importing data using M script. There are about 12 tables in the cube, SQL profiler shows 2 of them completed and the rest have starts but no completions. Something is hanging and can't figure out how to debug. Any suggestions?
In the end the only resolution that we had was to abandon the new connection type that uses "M" and go back to the legacy connection as explained here. So far it has not hung.