RFR: 8252104: parallel heap inspection for ShenandoahHeap

Tue Sep 8 03:24:22 UTC 2020

- enable parallel heap inspecton for ShenandoahHeap
  - preliminary evaluation:
    Time of jmap histo on (8GB heap with 4GB objects)
    * before: 5.186s
    * after : 1.698s

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Commit messages:
 - 8252104: parallel heap inspection for ShenandoahHeap

Changes: https://git.openjdk.java.net/jdk/pull/67/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=67&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8252104
  Stats: 179 lines in 2 files changed: 179 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/67.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/67/head:pull/67

PR: https://git.openjdk.java.net/jdk/pull/67