Speaking as a person who has implemented numerous web specs, you generally do start with a close approximation to the actual spec - I believe my original Map/Set implementations in JSC were exactly that.
Once you have a complete and correct implementation, then you can actually measure things and work out the critical parts and make them perform reasonable well.
But it’s really hard to do perf work if you don’t already have a reference/known good implementation.
And that’s what LibWeb is doing, which is giving them a workable baseline. Certainly enough that I’ve seen a few Kling videos where he abLe to focus on perf issues. A lot of the core performance bottlenecks devolve to “cache more”, and then devolves to those most hallowed of problems: cache invalidation.
Once you have a complete and correct implementation, then you can actually measure things and work out the critical parts and make them perform reasonable well.
But it’s really hard to do perf work if you don’t already have a reference/known good implementation.
And that’s what LibWeb is doing, which is giving them a workable baseline. Certainly enough that I’ve seen a few Kling videos where he abLe to focus on perf issues. A lot of the core performance bottlenecks devolve to “cache more”, and then devolves to those most hallowed of problems: cache invalidation.