Continuing we will see what is QueryLogSampling
The QueryLogSampling property defines the frequency with which Analysis Services logs query statistics into the query log table. A default value of 10 means that 1 of every 10 queries would be captured. This reduces the query log table from growing too large. We have decided to go with 15.
How should we go about SSAS Service Account Permissions on the database server where the dbo.OlapQueryLog table resides?
The SSAS Service Account is the one which runs the SSAS service, and it can be found in services. We observed that giving just write permissions was not sufficient. We made it db_owner and it started working.