sitespeedio / sitespeed.io

sitespeed.io is an open-source tool for comprehensive web performance analysis, enabling you to test, monitor, and optimize your website’s speed using real browsers in various environments.
https://www.sitespeed.io/
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Observing high response times compared to what we see in waterfall graph #4229

Open sweety-18 opened 1 month ago

sweety-18 commented 1 month ago

Your question

I executed sitespeed scripts for a webpage to capture the loading time. I observed the fully loaded time as 5 seconds, whereas when I checked the waterfall graph, none of the requests took more than 1 second, and the entire loading completed within 1 second.

Can you please let me know why it is showing extra time even though the waterfall shows that the page loading happened within 1 second?

Screenshot 2024-07-16 at 1 23 23 PM Screenshot 2024-07-16 at 1 23 36 PM Screenshot 2024-07-16 at 1 28 13 PM
soulgalore commented 1 month ago

It's hard to say since I don't know how you run the test. Here's some guidance on how to write a bug report so I can act on it: https://www.sitespeed.io/documentation/sitespeed.io/bug-report/

It looks like the request happen but there's 127 seconds before the domContentLoaded time happens. That metrics is the time the browser takes to parse the document and execute deferred and parser-inserted scripts including the network time from the users location.

I would try to launch the same test in another browser and see if you get the same behaviour.