8266802: Shenandoah: Round up region size to page size unconditionally

[zhengyu123]

I would like to backport this patch to 16u.

Without this patch, Shenandoah may not create enough regions to cover whole heap, that results some of heap memory never used.

The original patch applies cleanly to 16u and passed new test in patch.

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Progress

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Issue

• JDK-8266802: Shenandoah: Round up region size to page size unconditionally

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk16u pull/120/head:pull/120
$ git checkout pull/120

Update a local copy of the PR:
$ git checkout pull/120
$ git pull https://git.openjdk.java.net/jdk16u pull/120/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 120

View PR using the GUI difftool:
$ git pr show -t 120

Using diff file

Download this PR as a diff file:
https://git.openjdk.java.net/jdk16u/pull/120.diff

[bridgekeeper]

👋 Welcome back zgu! 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]

This backport pull request has now been updated with issue from the original commit.

[openjdk]

@zhengyu123 This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8266802: Shenandoah: Round up region size to page size unconditionally

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 1 new commit pushed to the master branch:

• 5311c4d: 8267345: VM crashes during dumping classlist with -Xshare:dump option

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[mlbridge]

Webrevs

• 00: Full (b4469437)

[zhengyu123]

/integrate

[openjdk]

@zhengyu123 Since your change was applied there has been 1 commit pushed to the master branch:

• 5311c4d: 8267345: VM crashes during dumping classlist with -Xshare:dump option

Your commit was automatically rebased without conflicts.

Pushed as commit e0060a3.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.