ScopedValue performance declines as number of dynamic bindings increases

[Robert Engels]

Correction, that is not the case - I see a 3x compile time difference.

> On Jun 24, 2025, at 11:35 AM, Robert Engels <robaho at me.com> wrote:
> 
> The reason in the difference in the compile times is related to the number of error messages generated.
> 
> If you compile using —enable-preview you will see that the compile times are nearly identical.
> 
>> On Jun 24, 2025, at 11:08 AM, Aleksey Shipilev <shipilev at amazon.de> wrote:
>> 
>> 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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