[pizlonator]

I’m not sure that performance needs to constrain web engine design the way it traditionally has. The world has changed since the browser perf war started.

Just try disabling the JIT in a modern browser and you’ll find your UX is not really any worse.

HW has gotten faster than when the current browser perf wars kicked off. So it might be that to have a meaningfully useful browser engine alternative, perf won’t be the top concern. Compatibility will though, just because of the sheer number of features a modern browser engine supports.

And if you don’t have JIT, then it’s not clear if Spectre is even a meaningful concern.

[roca]

Those are interesting points, but disabling the JIT doesn't really change anything unless it means you can forgo site isolation, and that would be a very risky bet.

It may be that disabling the JIT is fine for users most of the time. However, that is also a tough call --- so easy for your competitors to beat you up with benchmarks, and there will be real use-cases (e.g. emulators) where it matters to some users.

And of course there's a lot more to perf than just the JIT. I barely mentioned JIT in my blog post.

[coldtea]

>and there will be real use-cases (e.g. emulators)

Those are so niche as a concern, that might as well not take into account at all when doing a new browser engine.

[pizlonator]

Yeah but you mentioned Spectre. It’s not clear if you can do a Spectre attack on an interpreter. Maybe you can, but it seems super hard and not practical.

And without Spectre, the argument for site isolation is much weaker.