RFR: 8344593: GenShen: Review of ReduceInitialCardMarks

[Aleksey Shipilev]

On Tue, 3 Dec 2024 02:41:26 GMT, Y. Srinivas Ramakrishna <ysr at openjdk.org> wrote:

> Fix documentation comment.
> 
> I also checked the impact of +/-ReduceInitialCardMarks on GenShen using SPECjbb and didn't see any difference. We've left it enabled by default because less card marking is better in this case.

I still don't quite understand if we need to implement `CardTableBarrierSet::on_slowpath_allocation_exit`. I see `SharedRuntime::on_slowpath_allocation_exit` is called from different places in VM. Are those really subsumed by safepoints?

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

PR Comment: https://git.openjdk.org/jdk/pull/22507#issuecomment-2514996606