Monitoring SPO (and Onedrive!) performance and slowness:

  • The F12 tool bar network monitor or using third-party tool like fiddler or equivalent

  • SharePoint Online response header metrics (SPRequestDuration and X-SharePointHealthScore)

     SharePoint response header information

  1. Ensure that you have the F12 tools installed. For more information on downloading and installing these tools, see What’s new in F12 tools.

  2. In the F12 tools, on the Network tab, press the green play button to load a page.

  3. Click one of the .aspx files returned by the tool and then click DETAILS.Shows details of the response header
  4. Click Response headers.

    Diagram showing the URL of the response header