alt Hacker NewsRunning code by itself isn't that bad, it's the fact that browser developers have decided for some reason that this code needs to be as performant as possible, so, JIT.
I don't get it! The way JS is typically used, it doesn't even benefit from JIT all that much. Making ajax requests, doing stuff with strings, and moving DOM elements around doesn't need every CPU clock cycle to be used as optimally as possible. It's exceedingly rare for websites to actually be doing something that needs raw performance. And SPAs will be slow no matter what.
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Agree. Chrome should just disable JIT by default and boom many website owner will start to optimize their website.
> SPAs will be slow no matter what.
Uh…no?
You’re presumably talking about specific terrible prebuilt frameworks - not someone building a nice vanilla SPA.
I disagree about JIT performance not mattering. I enabled "Lockdown Mode" on iOS which disables the JIT for the mentioned security reasons, and it causes a very noticeable lagginess on many sites. Of course, the primary cause is the unnecessary JS monstrosities wasting CPU cycles. But practically speaking I can say that disabling the JIT results in a very subpar experience of many JS heavy pages.