[tzs]

Faster at what things?

On my 2017 iMac (3.4 GHz Core i5, Radeon Pro 570) I get 60 on Mozilla's Speedometer 2.0 [1] test with Firefox 57.0. I get 90 on Chrome and 93 on Safari.

On my Surface Pro 4 that gap is smaller, but Chrome is still about 15% faster on that test.

[1] https://mozilla.github.io/arewefastyet-speedometer/2.0/

[callahad]

Benchmarks are not comprehensive, nor are they gospel; it's entirely possible for a browser to score lower on a benchmark while also feeling faster in real-world use. For a long time, this was true of Chrome versus Firefox on JavaScript benchmarks: SpiderMonkey is routinely on par with V8, yet Firefox also felt significantly slower.

In the case of Speedometer, it's measuring one specific type of webapp interaction in a single tab; it's not capturing things like perceived speed of opening or closing the browser, switching tabs, loading pages, etc. It doesn't test how the browser performs when many JS-heavy tabs are loaded in the background. It also has lots of corner cases: installing a common password manager halves the score, and a common adblocker nearly does the same again, yet neither show that kind of noticeable degradation in real-world browsing.

Benchmarks are useful for saying "we've improved our browser this much in this area compared to where we were last year," but they're much less useful for making broad generalizations across heterogeneous browsers; there are too many other variables at play.

[Manishearth]

Whilst benchmarking stylo for example we noticed there were perceptible wins on interaction time on real world sites; but speedometer didn't budge as much because it tends towards small DOM trees which stylo can't parallelize much.

[ko27]

Yeah, they even recently officially posted the speedometer result and it was a few percent behind Chrome. Also some consider Speedometer to be the closest thing to a real user performance benchmark.