Recently QGIS is always very slow (or better freezing) when I am connected to the internet. Some processes take several minutes (even when opening or clicking on a dropdown menu from the taskbar). As soon as I disconnect my internet everything works fine and as usual. Is there an option in the settings to deny QGIS access to the internet. I have already deactivated the display of news and the search for updates. I use QGIS 3.16.4.
Three things that might cause such a slowdown:
- Accessing slow-ish layers over the internet, even if they're not on top/visible. One thing to try is to turn on the Debugging/Development tools panel (right click on the top toolbar to choose what panels are on/off). Then click on the red dot to log network activity. That way you can see what network requests are being sent -- to help you debug what layer(s) might be slowing you down that you might want to remove. This is what it looks like:
You will need to do the detective work to figure out what might be triggering each request, but hopefully the URL will help.
Layers or other info that does not load, due to server being down, leading to a long wait before timeouts. Especially if this is a recent server issue, it might slow things down in unexpected new ways. To get around this, you can drastically reduce the
Timeout for network requestssetting in
Settings / Options / Network.
There have in prior QGIS version with long timeout issues in the Browser panel accessing network paths that are offline, which could be resolved by disconnecting the laptop from the 'net so that the request failed immediately rather than timing out. I believe those issues have been fixed, but you could see if you problem goes away by turning off the Browser panel.
This Link suggests that you can turn off all the external connections within your desktop manuaally. In my case QGIS is extremely slow, since my pc is connected with multiple external servers. I right clicked in each one in the browser panel in qgis and hid/disconected from the browser.