Power BI slow report performance

Hi fnifdalizada  - Combine the 17 Excel sheets into a single table or fact table in your Power BI data model if possible. Add a column to differentiate each sheet (e.g., "Sheet Name" or "Category"). This reduces the number of queries Power BI has to process.

a. Remove Unnecessary Columns
Only load columns that are required for your visuals and calculations into the data model.
b. Partition Large Tables
If your Excel data has millions of rows, consider partitioning it into smaller chunks and filtering during load.
c. Optimize Query Folding
Ensure that Power Query transformations allow query folding (delegating operations back to the data source, such as SQL queries).
d. Data Refresh Strategy
Use incremental refresh to load only new or updated data instead of refreshing the entire dataset.

reference links:

Optimization guide for Power BI - Power BI | Microsoft Learn

PowerBI Report Server Performance Tuning Best Practices (PBIRS)