RFR: JDK-8180450: secondary_super_cache does not scale well [v5]

[Chris Plummer]

On Tue, 26 Mar 2024 12:02:37 GMT, Andrew Haley <aph at openjdk.org> wrote:

> [runtime/LoaderConstraints/itableICCE/Test.java] 
[serviceability/dcmd/vm/ClassHierarchyTest.java]: Test of diagnostic command VM.class_hierarchy
> 
> The only difference is the order of the interfaces. I think the tests may be invalid, but I'm not sure.

These are not SA tests. If these failures are in addition to SA failures, please tell me how you are running the tests, because I'm not seeing them fail, even with the edits you mention above and running with "-XX:+HashSecondarySupers -XX:+UseSecondarySuperCache". This includes the two tests you mention above. They both pass for me.

`serviceability/dcmd/vm/ClassHierarchyTest.java` does appear to rely on the interface order. It doesn't look like it will be hard to fix.

I don't see any obvious indication that `runtime/LoaderConstraints/itableICCE/Test.java` depends on interface order, but it is possible that it does in some subtle way. You'll need to get help from someone on the runtime team.

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PR Comment: https://git.openjdk.org/jdk/pull/18309#issuecomment-2021925546