The additional performance from the JIT is actually really small for most tasks. It should, ideally, be disabled by default. For your average JS you get <10% performance gain. Most of the cost is browser API, not JS, so the performance is underwhelming.
It’s only very heavy calculations that see a boost in performance. But, realistically, how many websites require this or currently use this today? <1%? Maybe <.1%?
This is pretty typical across JIT engines, too. PHP also sees only a slight increase in performance from the JIT. Because of the nature of PHP applications, most time is spend on the network and database. Only very CPU-heavy code sees a significant speed up.
That’s even the case for C#, which is why the dotnet runtime only conditionally JIT compiles code. Only hot path code is eligible for JIT compilation.
It’s only very heavy calculations that see a boost in performance. But, realistically, how many websites require this or currently use this today? <1%? Maybe <.1%?
This is pretty typical across JIT engines, too. PHP also sees only a slight increase in performance from the JIT. Because of the nature of PHP applications, most time is spend on the network and database. Only very CPU-heavy code sees a significant speed up.
That’s even the case for C#, which is why the dotnet runtime only conditionally JIT compiles code. Only hot path code is eligible for JIT compilation.