SSAS Tabular Loading Partitions from Stored Procedure not running in Parallel

Question

I have a Tabular Model table that contains multiple partitions governed by year. The partitions are all loaded by executing the same stored procedure and providing a year parameter to the stored procedure. The stored procedure has some data processing steps before it begins returning data. It takes about 10 minutes to begin returning data.

If we attempt to process 5 partitions (years) in parallel, we're seeing SSAS wait for the stored procedure to begin returning data for one partition before moving to the next partition. It's not running in parallel.

I'm trying to determine if this is normal behaviour for SSAS Tabular. I know it supports parallel processing of partitions, and this seems to work as long as the provisioning query immediately begins returning data. But if the partition is provisioned using a stored procedure, and that procedure has work to do, SSAS does not attempt to execute in parallel.

I've confirmed in SSMS that my Tabular Database Datasource Connection has multiple connections enabled (10).

Thanks for any insight.

Answer 1

Parallel partition processing was new as of Analysis Services 2016 Tabular models. If you are using 2012-2014 then you won’t get parallel partition processing (within a single table) and should upgrade.