The TBT metric value is relatively high in the sitespeed test results.

[heavenmyth]

Your question

The TBT metric value is relatively high in the sitespeed test results.

When using Lighthouse, the TBT is around 200ms, but in the sitespeed test, the TBT is around 600ms.

[soulgalore]

Hi @heavenmyth TBT depends on the CPU speed on the server where you run the tests. Do you run both tests on an isolated server or do they run on different machines? Do you set the CPU speed on the machine when you run the tests?

[heavenmyth]

HI @soulgalore ，Thank you for your response
I conducted the tests on the same Mac computer, which has an Intel chip. The difference is that Sitespeed was run using a Docker image, while Lighthouse was run directly in the browser.

The Docker command executed is: docker run -e MAX_OLD_SPACE_SIZE=4096 --shm-size=4g --rm -v "$(pwd):/sitespeed.io" sitespeedio/sitespeed.io:35.3.1-plus1 urls.txt -b chrome --config config.json

[soulgalore]

Yeah Docker adds some overhead.