What is the first action to take when using Power BI Desktop Performance Analyzer to ensure the data engine cache does not impact test results?

The first action to ensure that the data engine cache does not impact test results when using Power BI Desktop Performance Analyzer is to invoke the Clear Cache function. This is important because the data engine cache stores the results of previous queries and computations, which can lead to misleading performance metrics during testing. If the cache is not cleared, subsequent queries might return results more quickly than they normally would, as they benefit from cached data rather than reflecting the true performance of the underlying model and DAX calculations.

By clearing the cache, each query is executed fresh against the data model without relying on any cached results, providing a more accurate representation of performance. This allows users to analyze the performance of their DAX queries and reports without the influence of prior executions, leading to better insights and optimizations.

While other actions might have their utility, such as connecting DAX Studio to the data model for deeper analysis or invoking functions related to metadata or blank pages, these do not directly address the crucial aspect of isolating performance measurements from cached data. Therefore, the Clear Cache function is essential for obtaining reliable and valid performance results.