Power BI Desktop - Performance Issues

[SettlerOfCatan]

Hi everyone,

I’m having huge performance issues in Power BI Desktop, presumably coming from my web data requests. I’ve set up a bit more than 20 web data requests within one Power BI file, extracting data from web tables or csv files, all of them based on URL links. 

After getting these data in Power BI, I’ve carried out some basic transformation steps for each table like changing column types, deleting columns/rows, adding new columns, grouping, etc.

For some reason the loading of the web data (even in the Power Query mode) takes ages, at least 2-3 hours – in the meantime, my laptop doesn’t react at all which is annoying! The data tables I’m loading are not that complex – I’m not loading any big data tables – the pbix file only has about 500 KB. However, as soon as I open the pbix file and the data is loaded, the load factors both of my CPU and my main storage jump up to almost 100%, loading about 20 000 MB/s.

Attached you’ll find a video that demonstrates all this and shows more in detail what happens, as soon as I open the file.

Also interesting, once the data is loaded, all works perfectly again, however, it’s quite a tough and time-intensive path to get there.

Did anyone experience similar issues or do you have any suggestions on how to fix this?

Many thanks in advance for your input!

Picture:

Video and PowerBI file:
Sharepoint 

With best regards

SettlerOfCatan

@amitchandak 

[lbendlin]

Do your basic transformations include table merges?  Are these data sources impacted by the formula firewall? Have you disabled data previews? Have you used Binary.Buffer or Table.Buffer in your queries?

[SettlerOfCatan]

Q: Do your basic transformations include table merges?
A: Table merges are included.

Q: Are these data sources impacted by the formula firewall?
A: I do not think so, but I am not sure. How can I find this out?

Q: Have you disabled data previews?
A: Yes - no change

Q: Have you used Binary.Buffer or Table.Buffer in your queries?
A: I do not know what these things are. I use the default settings.

[lbendlin]

Try to avoid merges. Do the joining in the data model instead.

Buffers are your friend. They help you avoid pulling the same data multiple times.