8321013: Parallel: Refactor ObjectStartArray

[albertnetymk]

Port the block-offset-table algorithm from Serial/G1 to Parallel.

There is ~20% reduction in young-gc pause, using card_scan.java from https://bugs.openjdk.org/browse/JDK-8310031

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Issue

• JDK-8321013: Parallel: Refactor ObjectStartArray (Enhancement - P4)

Reviewers

• Thomas Schatzl (@tschatzl - Reviewer)
• Stefan Johansson (@kstefanj - Reviewer)

Reviewing

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[bridgekeeper]

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[openjdk]

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• 02: Full - Incremental (1cdec097)
• 01: Full (4c36f5e6)
• 00: Full (f6e8a311)

[tschatzl]

Lgtm!

It would be nice to consolidate the three implementations (Serial, Parallel and G1) as they differ in details in a separate CR.

[openjdk]

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

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8321013: Parallel: Refactor ObjectStartArray

Reviewed-by: tschatzl, sjohanss

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

• 7fbfb3b: 8321369: Unproblemlist gc/cslocker/TestCSLocker.java

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[kstefanj]

Looks good.

[albertnetymk]

Thanks for the review.

/integrate

[openjdk]

Going to push as commit 50baaf4.
Since your change was applied there have been 15 commits pushed to the master branch:

• afb8964: 8320443: [macos] Test java/awt/print/PrinterJob/PrinterDevice.java fails on macOS
• 82796bd: 8320570: NegativeArraySizeException decoding >1G UTF8 bytes with non-ascii characters
• 781775d: 8321484: Make TestImplicitlyDeclaredClasses release independent
• b02fc86: 8321122: Shenandoah: Remove ShenandoahLoopOptsAfterExpansion flag
• 2830dd2: 8321410: Shenandoah: Remove ShenandoahSuspendibleWorkers flag
• f482260: 8319969: os::large_page_init() turns off THPs for ZGC
• 3edc24a: 8321073: Defer policy of disabling annotation processing by default
• dc9c77b: 8318756: Create better internal buffer for AEADs
• a9cb120: 8320948: NPE due to unreported compiler error
• 4ef24e2: 8319938: TestFileChooserSingleDirectorySelection.java fails with "getSelectedFiles returned empty array"
• ... and 5 more: https://git.openjdk.org/jdk/compare/2678e4cd9424ca4e33ebb9693c84f9a86bf5504c...master

Your commit was automatically rebased without conflicts.

[openjdk]

@albertnetymk Pushed as commit 50baaf4.

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