RFR: 8272364: Parallel GC adaptive size policy may shrink the heap below MinHeapSize [v2]

[Zhengyu Gu]

> This appears to be another miscalculation of gc ergonomics. When `NewSize` is not explicitly set, `MinNewSize` should be derived from `MinHeapSize` using `NewRatio`.
> 
> This pull request has dependency on [PR#18539](https://github.com/openjdk/jdk/pull/18539)

Zhengyu Gu has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains eight additional commits since the last revision:

 - 8272364: Parallel GC adaptive size policy may shrink the heap below MinHeapSize
 - Albert's comment
 - Make sure MinOldSize <= OldSize when it is set on the command line
 - Merge branch 'master' into JDK-8329223
 - albertnetymk's suggestion
 - Merge branch 'master' into JDK-8329223
 - Cleanup
 - 8329223: Parallel: Parallel GC resizes heap even has -Xms = -Xmx

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Changes:
  - all: https://git.openjdk.org/jdk/pull/18877/files
  - new: https://git.openjdk.org/jdk/pull/18877/files/dde348df..dde348df

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=18877&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18877&range=00-01

  Stats: 0 lines in 0 files changed: 0 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/18877.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18877/head:pull/18877

PR: https://git.openjdk.org/jdk/pull/18877