RFC: JEP draft: Ergonomics Always Select the G1 Garbage Collector as Default

[Kirk Pepperdine]

Hi Thomas,

I believe I did mentioned that I have benchmarks that do better with the serial collector with smaller heaps. It isn’t an outright objection but more of another data point.

Kind regards,
Kirk


> On Jun 23, 2025, at 1:57 AM, Thomas Schatzl <thomas.schatzl at oracle.com> wrote:
> 
> Hi all,
> 
>  this is a continuation of an earlier thread [0] where I suggested to make G1 as the default collector unconditionally.
> 
> As you may know, on very small deployments (1 CPU and 1.8GB of heap), ergonomics still select the Serial collector if no GC algorithm is selected on the command line.
> 
> Since there has not been any pushback to that suggestion, I wrote up a JEP draft [1], so I wanted to ask for further feedback before submitting it.
> 
> Thanks,
>  Thomas
> 
> [0] https://mail.openjdk.org/pipermail/hotspot-gc-dev/2025-February/051121.html
> [1] https://bugs.openjdk.org/browse/JDK-8359802