Withdrawn: 8347717: Small MaxHeapSize gets increased a lot on platform with large page size

[Martin Doerr]

On Tue, 14 Jan 2025 16:01:42 GMT, Martin Doerr <mdoerr at openjdk.org> wrote:

> `GCArguments::compute_heap_alignment()` is currently problematic for platforms with large page size. E.g. on PPC64 with 64k pages:
> `java -XX:+PrintFlagsFinal -Xmx8m -version |grep -E "GCCardSizeInBytes|MaxHeapSize"` says:
> 
>      uint GCCardSizeInBytes                        = 512                                       {product} {default}
>    size_t MaxHeapSize                              = 33554432                                  {product} {command line, ergonomic}
>    size_t SoftMaxHeapSize                          = 33554432                               {manageable} {ergonomic}
> openjdk version "25-internal" 2025-09-16
> 
> 
> 
> I suggest to adapt `GCCardSizeInBytes` such that we get the following in this case:
> 
>      uint GCCardSizeInBytes                        = 128                                       {product} {ergonomic}
>    size_t MaxHeapSize                              = 8388608                                   {product} {command line}
>    size_t SoftMaxHeapSize                          = 8388608                                {manageable} {ergonomic}
> 
> 
> Please review. Are there good alternatives / other proposals?

This pull request has been closed without being integrated.

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PR: https://git.openjdk.org/jdk/pull/23107