Data Flow Slow Refresh

[Anonymous]

Hello folks!

First time poster but long time visitor of the forums.

Recently I migrated one of my larger data models (about 16 entities from roughly 6 source files) into a data flow so it can be used with multiple datasets. However; my refresh times have since sky rocketed. When working with the dataset in desktop, I got a refresh time of roughly 30 seconds; versus now, which takes about 15 minutes to refresh. I took a look at the refresh log, and there isn't one entity holding the whole thing up, its just the bigger entities take 2-3 minutes, and the smaller ones take 1 or less.

Some details:

 - All queries are coming from a "web source" sharepoint folder, both now and before

 - The largest chunk of data is only 25k rows

 - Some entities are coming from other entities (query in a table of data, and then multiple different queries use that query as their source)

 - There are a lot of expansion transformations (splitting rows, not just columns)

From what I've read, data flows are supposedly faster than power query in desktop, so I was wondering if anyone else has had some trouble or advice.

[GilbertQ · Accepted solution]

Hi there

Typically it is slower when using dataflows especially with a lot of transformations because using shared capacity it is sharing the memory and CPU. Whilst when you do this on desktop you got dedicated CPU and memory.

If there is no issue with it taking longer to refresh I would then leave it as is, yes it is taking longer but there is no impact to the reports.