Power BI Premium with Composite Models

hello powerbihelp87 

When using a composite model that combines DirectQuery and Import data sources, Power BI Premium handles the integration of these data sources. While DirectQuery queries are executed on the source system (e.g., AAS), Power BI must process and combine the results with data from imported tables locally. This integration, including any DAX calculations or relationships between the sources, occurs within the Power BI Premium Capacity and contributes to its resource usage

While AAS handles its own query execution for DirectQuery models, Power BI’s composite model architecture requires additional processing within Power BI itself:
• The results from AAS queries are fetched into Power BI for further processing (e.g., combining with imported data). This processing happens within the Premium Capacity and contributes to its load.
• Any inefficiencies in DAX measures or relationships in the Power BI model will amplify resource usage on the Premium Capacity rather than offloading entirely to AAS

Hope this clarifies why high capacity usage. 

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