[jdk17u-dev] RFR: 8343205: CompileBroker::possibly_add_compiler_threads excessively polls available memory [v2]

[Martin Doerr]

> Backport of [JDK-8343205](https://bugs.openjdk.org/browse/JDK-8343205) from jdk21u-dev.

Martin Doerr 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 two additional commits since the last revision:

 - Merge remote-tracking branch 'origin' into 8343205_possibly_add_compiler_threads
 - Backport 3087c6c74d742b7b5eaf28e4c886b5dc1811ea6f

-------------

Changes:
  - all: https://git.openjdk.org/jdk17u-dev/pull/3106/files
  - new: https://git.openjdk.org/jdk17u-dev/pull/3106/files/a320a4b7..ac1b0926

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=3106&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=3106&range=00-01

  Stats: 40722 lines in 781 files changed: 21596 ins; 11010 del; 8116 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/3106.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/3106/head:pull/3106

PR: https://git.openjdk.org/jdk17u-dev/pull/3106