RFR: 8348309: MultiNST tests need more debugging and timing [v2]

[Anthony Scarpino]

> I need a review of this change that adds new timing controls for the initial server setup.  On rare occasions, more so on certain architectures, the server may not fully start before the client tries to connect.  Additional debugging is added to help identify if there are other timing issues.
> 
> Thanks
> 
> Tony

Anthony Scarpino has updated the pull request incrementally with one additional commit since the last revision:

  review comments

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Changes:
  - all: https://git.openjdk.org/jdk/pull/23407/files
  - new: https://git.openjdk.org/jdk/pull/23407/files/0a0a7365..3ec8d051

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23407&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23407&range=00-01

  Stats: 3 lines in 2 files changed: 0 ins; 2 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/23407.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23407/head:pull/23407

PR: https://git.openjdk.org/jdk/pull/23407