[jdk21u-dev] RFR: 8180450: secondary_super_cache does not scale well [v2]

[Andrew Haley]

> See [8180450](https://github.com/openjdk/jdk/pull/18309) for a full description of how this works.
> This is a pretty clean backport, but a few files had to be fiddled manually because things had been added nearby.
> 
> This PR also includes a fix for [[8337958](https://bugs.openjdk.org/browse/JDK-8337958)](https://bugs.openjdk.org/browse/JDK-8337958), which was a minor bug in the original commit.
> 
> For a justification of why this PR should be backported to JDK 21u, see 
> [Franz's email](https://mail.openjdk.org/pipermail/jdk-updates-dev/2024-October/038649.html).

Andrew Haley has updated the pull request incrementally with one additional commit since the last revision:

  Add check

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Changes:
  - all: https://git.openjdk.org/jdk21u-dev/pull/1090/files
  - new: https://git.openjdk.org/jdk21u-dev/pull/1090/files/983b05e3..cfce5b29

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1090&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1090&range=00-01

  Stats: 5 lines in 1 file changed: 5 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1090.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1090/head:pull/1090

PR: https://git.openjdk.org/jdk21u-dev/pull/1090