RFR: 8348858: [leyden] Bump the default code buffer sizes to store more generated code [v4]

[Aleksey Shipilev]

On Fri, 31 Jan 2025 17:28:24 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

>> Due to current prototype limitation, we cannot yet store the generated code that has the expanded code buffer. I tried to address that directly, but I think relocations disagree with the whole thing, so this implementation limitation stays for a bit longer. I turned the bailout due to that cause from `info` into `warning`.
>> 
>> On `JavacBenchApp 50`, this causes us to lose 700 (!) C2 compiled methods from the SCC! We can dodge significant part of the hit by bumping the default code buffer sizes, and thus making buffers less likely to require resizing, and thus allowing to store more code in SCC. 
>> 
>> Additional testing:
>>  - [x] Linux x86_64 server fastdebug, `runtime/cds`
>
> Aleksey Shipilev has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Trying to conditionalize the whole thing for SCC write path (untested)

I think this still does the right thing performance-wise, but I can only judge based on compilation logs. I'll see if GHA is green, and then see if we can integrate.

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PR Comment: https://git.openjdk.org/leyden/pull/28#issuecomment-2628041890