RFR: 8361076: Add benchmark for ImageReader in preparation for Valhalla changes [v3]

[David Beaumont]

On Wed, 16 Jul 2025 06:03:28 GMT, Alan Bateman <alanb at openjdk.org> wrote:

>> Debatable. It's obviously going to scale any results somewhat based on the size of the resources and number of classes. It's kind nice to see "this change removes at least N micro/milli seconds of time spent" since that's a minimum set of classes we expect to always be needed, so any time saved is a lower bound.
>> 
>> I'd say maybe leave it as is for now with a note saying "if this keeps breaking, make the list less fragile".
>> I'm also assuming this is only run manually, and not a part of any CI pipeline ... so please let me know if I'm wrong about that.
>
> lib/classlist is used to generate the AOT archive, I wonder if a `@Setup` could be used to consume that to create the INIT_CLASSES.

I will look at that as a followup action. I'd rather get this in to unblock the main ImageReader refactoring.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/26044#discussion_r2210172307