performancegoogle-chromeoptimizationlighthouse

Why DevTools throttling options are not changing my Lighthouse performance?


Every resource I can find about why Lighthouse performance scores are vastly different than desktop says it's because the bandwidth/throttling is set to 3G (still?), but changing the throttling settings doesn't change the performance rating for me. Am I using it wrong?

In the Lighthouse tab I select DevTools throttling (advanced):

enter image description here

There are no further settings after selecting the option, so I am presuming it uses whatever I have set in the Network tab, which is set for no throttling:

enter image description here

My other throttling options also do not affect the performance rating.

Could this be a browser bug?


Solution

  • Lighthouse has changed with the Update on august 2022. I found that they replaced the noThrottling option, with advanced Throttling. Unforgently the advanced Throttling setting will only affect the Trace display and not the performance score, as i understand it. THUS THE SCORE WILL ALLWAYS be affected by the simulated Throttling. Terrible product policy...

    Lighthouse manual says:

    The Lighthouse panel has a simplified throttling setup:

    Simulated throttling remains the default setting. This matches the setup of PageSpeed Insights and the Lighthouse CLI default, maintaining cross-tool consistency.
        If you click the View Original Trace button, the trace values will not match up with Lighthouse's metric results, as the original trace is prior to the simulation.
    Applied throttling is available within the Lighthouse panel settings (⚙): uncheck the Simulated throttling checkbox.
        In this mode, the performance data seen after clicking the View Trace button will match Lighthouses's numbers.
    

    Find the documentation here: enter image description here