8266352: Add parallel heap iteration for jmap –histo

[buddyliao]

8215624: Add parallel heap iteration for jmap -histo
8251570: JDK-8215624 causes assert(worker_id <' _n_workers) failed: Invalid worker_id
8253763: ParallelObjectIterator should have virtual destructor

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Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change must be properly reviewed

Integration blocker

 ⚠️ Issue of type Backport is not allowed for integrations

Issue

• JDK-8266352: Add parallel heap iteration for jmap –histo

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk11u-dev pull/75/head:pull/75
$ git checkout pull/75

Update a local copy of the PR:
$ git checkout pull/75
$ git pull https://git.openjdk.java.net/jdk11u-dev pull/75/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 75

View PR using the GUI difftool:
$ git pr show -t 75

Using diff file

Download this PR as a diff file:
https://git.openjdk.java.net/jdk11u-dev/pull/75.diff

[bridgekeeper]

👋 Welcome back buddyliao! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

⚠️ @buddyliao a branch with the same name as the source branch for this pull request (master) is present in the target repository. If you eventually integrate this pull request then the branch master in your personal fork will diverge once you sync your personal fork with the upstream repository.

To avoid this situation, create a new branch for your changes and reset the master branch. You can do this by running the following commands in a local repository for your personal fork. Note: you do not have to name the new branch NEW-BRANCH-NAME.

$ git checkout -b NEW-BRANCH-NAME
$ git branch -f master 52cbf2f653a9d36932f16ccbab7b61a1918cd18e
$ git push -f origin master

Then proceed to create a new pull request with NEW-BRANCH-NAME as the source branch and close this one.

[buddyliao]

/jdk11u-fix-request

[mlbridge]

Webrevs

• 01: Full - Incremental (52cbf2f6)
• 00: Full (3bcb48cb)

[buddyliao]

Fix Request

[RealCLanger]

Hi @buddyliao, can you this backport in 3 separate PRs? I think none of these breaks the build so it's ok to go one by one. Thanks!