Power Bi Refresh Slow - How to troubleshoot

[jscr626]

I have a user who has created a dataset consisting of CSV files sent to a SharePoint library from a nightly export. When using Power BI desktp, the refreshes on these files take a few seconds. When published to the Power BI service, the schedules refreshes each take 30 min to 1 hour. The issue is these are sometimes not completing for beginning of the business day.

What would be the reason for this difference? I'm assuming it's resource related, but is there anything we can do to speed up these refreshes from an admin side? Troubelshooting tips?

[v-yanjiang-msft · Accepted solution]

Hi @jscr626  ,

There are many aspects to troubleshoot the problem.
1. As you say, for the data source, do the follow steps:

• Model your data properly, always build a star schema!
• Remove/filter all data that isn’t needed for your report/analysis before loading into Power BI.
• Calculated columns and calculated tables are evaluated during refresh, can you replace a calculated column with a measure and avoid complicated operations.

2. Free and Pro user will refresh their reports in shared capacity, as we know shared capacity will has limitation in refresh rate, stroage mode and so on.

If we need better peformance in refresh like larger refresh rate or bigger stroage mode, we need to purchase Premium. You can find the comparation between Pro and Premium in this link: Explore Power BI plans

3. Consider using incremental refresh. Incremental refresh lets you refresh only the data that is new or has changed, refer to the this blog fot detailed steps.

4. Using dataflows to improve performance. Dataflows let you share the output of a Power Query query between multiple datasets. It do complex transformations once instead of inside multiple datasets and do transformations when the data for one query is ready, no need to wait until all data needed by the dataset is ready. Refer to this blog: How to Use Dataflow to Make the Refresh of Power BI Solution FASTER! - RADACAD

5. If you are using an on-premises data gateway to load data, locate the gateway machine close to the data source, make sure the gateway server has enough CPU and memory. Clustered gateways allow for the load to be spread across multiple servers.

Refer to this blog for more information.

Best Regards,
Community Support Team _ kalyj

If this post helps, then please considerAccept it as the solution to help the other members find it more quickly.

[GilbertQ]

Hi @jscr626 

Because this is using the Power BI Service, it is using shared resources

What you could do, is to install an on-premise gateway and see if that speeds up the refresh?

This is because the actual refreshing part will be completed on the On-Premise gateway hardware which you will own and look after.