ScopedValue performance declines as number of dynamic bindings increases

[Aleksey Shipilev]

On 24.06.25 18:01, Johan Sjolen wrote:
> Oooh, that could explain the issue completely. I didn't think about that at all.
> The issue basically disappears when compiling first, let me see what happens with a JMH benchmark as well.

I predict JMH would show the same thing.

javac is not very fast when cold; this is also why we use it as go-to example in AOT cache studies. 
I would also expect compiling deeply nested lambdas (like in ScopedTest.java) makes the javac code 
fairly recursive, which again plays interestingly with JIT compilation. It is still 
actionable/interesting to figure out what can be improved there. Looks fairly weird we spend >3 
seconds compiling a seemingly "easy" source. Submit a tools/javac RFE, let compiler folks have fun 
with it?

-Aleksey



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