[jdk8u-dev] RFR: 8293562: KeepAliveCache Blocks Threads while Closing Connections [v5]

[Dhamoder Nalla]

> Issue: [JDK-8293562](https://bugs.openjdk.org/browse/JDK-8293562): KeepAliveCache Blocks Threads while Closing Connections
> Backport of PR https://github.com/openjdk/jdk11u-dev/pull/1890 fromJDK11 to JDK8.
> 
> The JDK11 patch doesn't apply cleanly 3/11 hunks need to be ported manually in KeepAliveCache.java.
> 
> Test performed:
> 
> 1. JTreg jdk_tier1
> 2. JTreg jdk_tier2
> 3. New test case added to this PR passed with the fix and failed without it.
> 4. The customer failure scenario has been validated.

Dhamoder Nalla has updated the pull request incrementally with one additional commit since the last revision:

  Fix white spaces

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

Changes:
  - all: https://git.openjdk.org/jdk8u-dev/pull/409/files
  - new: https://git.openjdk.org/jdk8u-dev/pull/409/files/36cb9124..0476345c

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=409&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk8u-dev&pr=409&range=03-04

  Stats: 19 lines in 1 file changed: 1 ins; 2 del; 16 mod
  Patch: https://git.openjdk.org/jdk8u-dev/pull/409.diff
  Fetch: git fetch https://git.openjdk.org/jdk8u-dev.git pull/409/head:pull/409

PR: https://git.openjdk.org/jdk8u-dev/pull/409