8261251: Shenandoah: Use object size for full GC humongous compaction

[shipilev]

This fixes a minor performance issue in Shenandoah (which becomes asserted in later projects, i.e. Loom).

Additional testing:

• hotspot_gc_shenandoah

---

Progress

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

Issue

• JDK-8261251: Shenandoah: Use object size for full GC humongous compaction

Reviewers

• Zhengyu Gu (@zhengyu123 - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jdk16u pull/55/head:pull/55
$ git checkout pull/55

[bridgekeeper]

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[openjdk]

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

[mlbridge]

Webrevs

• 00: Full (cde81c3)

[openjdk]

@shipilev 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:

8261251: Shenandoah: Use object size for full GC humongous compaction

Reviewed-by: zgu

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 no new commits pushed to the master branch. If another commit should be pushed before you perform the /integrate command, your PR will be automatically rebased. If you prefer to avoid any potential automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[shipilev]

/integrate

[openjdk]

@shipilev Since your change was applied there have been 6 commits pushed to the master branch:

• 39fb8e5: 8261413: Shenandoah: Disable class-unloading in I-U mode
• b9582bf: 8260048: Shenandoah: ShenandoahMarkingContext asserts are unnecessary
• f081554: 8259580: Shenandoah: uninitialized label in VerifyThreadGCState
• 395ab59: 8258490: Shenandoah: Full GC does not need to remark threads and drain SATB buffers
• cec5816: 8259954: gc/shenandoah/mxbeans tests fail with -Xcomp
• f36b10a: 8261170: Upgrade to freetype 2.10.4

Your commit was automatically rebased without conflicts.

Pushed as commit 101e742.

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