[jdk17u-dev] RFR: 8298381: Improve handling of session tickets for multiple SSLContexts

[David Schlosnagle]

I would like to propose a backport of [JDK-8298381](https://bugs.openjdk.org/browse/JDK-8298381) commit https://github.com/openjdk/jdk/commit/debe5879aa7118a114ff6fcf8d15951757ae70a8 that landed in JDK 21 to jdk17u. This change significantly improves TLS handshaking latency and throughput for services that utilize multiple `SSLContext`. As an example, Apache Kafka running on JDK 17 with significant numbers of clients may see over 40% of CPU utilization due to `SessionTicketExtension$KeyState.cleanup(HandshakeContext)`.

@simonis or others, would you be willing to sponsor this change to JDK 17u and create a corresponding JIRA ticket?

Thanks!

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Commit messages:
 - 8298381: Improve handling of session tickets for multiple SSLContexts

Changes: https://git.openjdk.org/jdk17u-dev/pull/2750/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2750&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8298381
  Stats: 143 lines in 3 files changed: 67 ins; 65 del; 11 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2750.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2750/head:pull/2750

PR: https://git.openjdk.org/jdk17u-dev/pull/2750