PowerPlatformDataflow Analysis request timed out before it was completed.

There is a hard 5 hour limit for semantic model refreshes. That's where the 18000 comes from.

The cause must be something else besides your dataflow.

Hi, nrichards_au 

Thanks for lbendlin reply. You can refer to his reply, troubleshooting if there are other issues affecting data stream refreshing. Even though the dataflow has previously loaded without issues, it's possible that changes in data volume or complexity have increased the processing time. Ensure that the dataflow is optimized for performance. This includes reviewing the dataflow design, such as the use of staging tables, the number of transformations, and the efficiency of these transformations. 

1. Consider using Incremental refresh for datasets that are larger than 1GB or take several hours to refresh.
Incremental refresh for semantic models and real-time data in Power BI - Power BI | Microsoft Learn

2. Verify that the data sources you are connecting to are performing well and that there are no network issues that could be causing delays in data retrieval.
3. Use monitoring tools within Power Platform to track the performance of your dataflow. This can help identify bottlenecks or long-running operations that may be causing the timeout.
Monitoring the Power Platform: Introduction and Index (dynamics.com)
4. If the dataflow is particularly complex or handling a large volume of data, consider splitting it into smaller, more manageable dataflows. This can sometimes help with performance issues.
Conditional split transformation in mapping data flow - Azure Data Factory & Azure Synapse | Microsoft Learn

Related links: 
Troubleshoot refresh scenarios - Power BI | Microsoft Learn
Solved: data refresh timeout - works sometimes, fails othe... - Microsoft Fabric Community
Solved: The XML for Analysis request timed out before it w... - Microsoft Fabric Community

Best Regards,
Yang
Community Support Team

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