8325754: Dead AbstractQueuedSynchronizer$ConditionNodes survive minor garbage collections

[neethu-prasad]

Notes
Backport of JDK-8325754.

Unlink 'ConditionNode' before they are transferred to the sync queue as G1 seems to be able to collect “dead” ConditionNode instances during minor collections only if no formerly alive ConditionNode instances were promoted to the old generation and died there, which often cannot be avoided since e.g. on application startup many objects are promoted to the old generation after a few collections.

Verification

• jdk_util, Tier 1 & Tier 2 tests passed.
• Ran G1LoiteringConditionNodes.java (sample code from bug description) and verified that YG GC time is not increasing after full GC.

Before PR

dev-dsk-neethp-jdk-2c-ad54955c % /home/neethp/Development/jdk17u-dev/build/linux-x86_64-server-release/images/jdk/bin/java -Xms2048m -Xmx2048m -XX:+UseG1GC -XX:+UnlockExperimentalVMOptions -XX:G1MaxNewSizePercent=20 '-Xlog:gc*,gc+age*=trace' -cp . G1LoiteringConditionNodes | grep -E 'Pause.*ms'
[0.960s][info ][gc          ] GC(0) Pause Young (Normal) (G1 Evacuation Pause) 102M->1M(2048M) 5.290ms
[2.485s][info ][gc          ] GC(1) Pause Young (Normal) (G1 Evacuation Pause) 149M->1M(2048M) 2.288ms
[6.805s][info ][gc          ] GC(2) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.393ms
[11.165s][info ][gc          ] GC(3) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.603ms
[15.544s][info ][gc          ] GC(4) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.462ms
[19.955s][info ][gc          ] GC(5) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.382ms
[24.369s][info ][gc          ] GC(6) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.246ms
[28.790s][info ][gc          ] GC(7) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.443ms
[33.211s][info ][gc          ] GC(8) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.331ms
[37.639s][info ][gc          ] GC(9) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.319ms
[42.066s][info ][gc          ] GC(10) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.629ms
[46.515s][info ][gc          ] GC(11) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.334ms
[50.957s][info ][gc          ] GC(12) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.280ms
[55.382s][info ][gc          ] GC(13) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.413ms
[59.830s][info ][gc          ] GC(14) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.061ms
[60.055s][info ][gc             ] GC(15) Pause Full (System.gc()) 26M->1M(2048M) 10.780ms
[64.482s][info ][gc             ] GC(16) Pause Young (Normal) (G1 Evacuation Pause) 410M->2M(2048M) 3.663ms
[68.893s][info ][gc             ] GC(17) Pause Young (Normal) (G1 Evacuation Pause) 410M->2M(2048M) 4.008ms
[73.297s][info ][gc             ] GC(18) Pause Young (Normal) (G1 Evacuation Pause) 409M->3M(2048M) 4.131ms
[77.699s][info ][gc             ] GC(19) Pause Young (Normal) (G1 Evacuation Pause) 410M->3M(2048M) 4.188ms
[82.106s][info ][gc             ] GC(20) Pause Young (Normal) (G1 Evacuation Pause) 410M->3M(2048M) 5.016ms
[86.509s][info ][gc             ] GC(21) Pause Young (Normal) (G1 Evacuation Pause) 409M->4M(2048M) 4.563ms
[90.907s][info ][gc             ] GC(22) Pause Young (Normal) (G1 Evacuation Pause) 410M->4M(2048M) 4.976ms
[95.292s][info ][gc             ] GC(23) Pause Young (Normal) (G1 Evacuation Pause) 409M->5M(2048M) 5.171ms
[99.671s][info ][gc             ] GC(24) Pause Young (Normal) (G1 Evacuation Pause) 410M->5M(2048M) 5.279ms
[104.050s][info ][gc             ] GC(25) Pause Young (Normal) (G1 Evacuation Pause) 410M->6M(2048M) 5.496ms
[108.418s][info ][gc             ] GC(26) Pause Young (Normal) (G1 Evacuation Pause) 410M->6M(2048M) 6.194ms
[112.784s][info ][gc             ] GC(27) Pause Young (Normal) (G1 Evacuation Pause) 410M->6M(2048M) 5.887ms
[117.147s][info ][gc             ] GC(28) Pause Young (Normal) (G1 Evacuation Pause) 409M->7M(2048M) 5.952ms
[121.505s][info ][gc             ] GC(29) Pause Young (Normal) (G1 Evacuation Pause) 410M->7M(2048M) 6.124ms
[125.846s][info ][gc             ] GC(30) Pause Young (Normal) (G1 Evacuation Pause) 409M->8M(2048M) 6.195ms
[130.192s][info ][gc             ] GC(31) Pause Young (Normal) (G1 Evacuation Pause) 410M->8M(2048M) 7.301ms

After this change

dev-dsk-neethp-jdk-2c-ad54955c % /home/neethp/Development/jdk17u-dev/build/linux-x86_64-server-release/images/jdk/bin/java -Xms2048m -Xmx2048m -XX:+UseG1GC -XX:+UnlockExperimentalVMOptions -XX:G1MaxNewSizePercent=20 '-Xlog:gc*,gc+age*=trace' -cp . G1LoiteringConditionNodes | grep -E 'Pause.*ms'
[0.983s][info ][gc          ] GC(0) Pause Young (Normal) (G1 Evacuation Pause) 102M->1M(2048M) 4.400ms
[2.474s][info ][gc          ] GC(1) Pause Young (Normal) (G1 Evacuation Pause) 146M->1M(2048M) 2.198ms
[6.783s][info ][gc          ] GC(2) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.725ms
[11.169s][info ][gc          ] GC(3) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.613ms
[15.543s][info ][gc          ] GC(4) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.207ms
[19.941s][info ][gc          ] GC(5) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.155ms
[24.360s][info ][gc          ] GC(6) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 1.993ms
[28.789s][info ][gc          ] GC(7) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.168ms
[33.217s][info ][gc          ] GC(8) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.291ms
[37.644s][info ][gc          ] GC(9) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.463ms
[42.071s][info ][gc          ] GC(10) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.533ms
[46.514s][info ][gc          ] GC(11) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.097ms
[50.961s][info ][gc          ] GC(12) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.460ms
[55.381s][info ][gc          ] GC(13) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.409ms
[59.817s][info ][gc          ] GC(14) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.716ms
[60.082s][info ][gc             ] GC(15) Pause Full (System.gc()) 27M->1M(2048M) 9.750ms
[64.502s][info ][gc             ] GC(16) Pause Young (Normal) (G1 Evacuation Pause) 410M->1M(2048M) 1.855ms
[68.917s][info ][gc             ] GC(17) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.130ms
[73.325s][info ][gc             ] GC(18) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 1.897ms
[77.733s][info ][gc             ] GC(19) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 1.963ms
[82.135s][info ][gc             ] GC(20) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 1.986ms
[86.545s][info ][gc             ] GC(21) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.204ms
[90.946s][info ][gc             ] GC(22) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 1.737ms
[95.359s][info ][gc             ] GC(23) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 1.858ms
[99.757s][info ][gc             ] GC(24) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 2.115ms
[104.161s][info ][gc             ] GC(25) Pause Young (Normal) (G1 Evacuation Pause) 409M->1M(2048M) 1.915ms

---

Progress

• JDK-8325754 needs maintainer approval
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8325754: Dead AbstractQueuedSynchronizer$ConditionNodes survive minor garbage collections (Bug - P4 - Approved)

Reviewing

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👋 Welcome back neethu-prasad! 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]

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

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

8325754: Dead AbstractQueuedSynchronizer$ConditionNodes survive minor garbage collections

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At the time when this comment was updated there had been 121 new commits pushed to the master branch:

• 3d83f3e: 8329109: Threads::print_on() tries to print CPU time for terminated GC threads
• 1e63af9: 8300806: Update googletest to v1.13.0
• e809008: 8300910: Remove metaprogramming/integralConstant.hpp
• 952d272: 8300265: Remove metaprogramming/isSigned.hpp
• f9acc53: 8300260: Remove metaprogramming/isSame.hpp
• 3069e3e: 8305959: x86: Improve itable_stub
• e43402d: 8335918: update for deprecated sprintf for jvmti
• 5d5ca9c: 8300264: Remove metaprogramming/isPointer.hpp
• 9b39fff: 8299971: Remove metaprogramming/conditional.hpp
• 89dd23f: 8299254: Support dealing with standard assert macro
• ... and 111 more: https://git.openjdk.org/jdk17u-dev/compare/9056b3bf10711e3a1a8cd91c4b33724f4e4aa9c0...master

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[openjdk]

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

[openjdk]

⚠️ @neethu-prasad This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[mlbridge]

Webrevs

• 00: Full (3a947ac7)

[neethu-prasad]

/approval request Backport to unlink 'ConditionNode' before they are transferred to the sync queue; applies cleanly; All tests passed; Risk is low: there are no follow-up bug since mainline integration 4 months ago. Also, similar change was made to LinkedBlockingQueue more than 10 years ago as part of JDK-6805775

[openjdk]

@neethu-prasad
8325754: The approval request has been created successfully.

[openjdk]

@neethu-prasad
Your change (at version 3a947ac) is now ready to be sponsored by a Committer.

[neethu-prasad]

Will integrate once backport to 21 is closed.
https://bugs.openjdk.org/browse/JDK-8334825

[phohensee]

/sponsor

[openjdk]

Going to push as commit 4c58e1b.
Since your change was applied there have been 125 commits pushed to the master branch:

• cfe714b: 8325194: GHA: Add macOS M1 testing
• 05bea0e: 8328158: Convert java/awt/Choice/NonFocusablePopupMenuTest to automatic main test
• 7dcb608: 8255898: Test java/awt/FileDialog/FilenameFilterTest/FilenameFilterTest.java fails on Mac OS
• c915eaf: 8280982: [Wayland] [XWayland] java.awt.Robot taking screenshots
• 3d83f3e: 8329109: Threads::print_on() tries to print CPU time for terminated GC threads
• 1e63af9: 8300806: Update googletest to v1.13.0
• e809008: 8300910: Remove metaprogramming/integralConstant.hpp
• 952d272: 8300265: Remove metaprogramming/isSigned.hpp
• f9acc53: 8300260: Remove metaprogramming/isSame.hpp
• 3069e3e: 8305959: x86: Improve itable_stub
• ... and 115 more: https://git.openjdk.org/jdk17u-dev/compare/9056b3bf10711e3a1a8cd91c4b33724f4e4aa9c0...master

Your commit was automatically rebased without conflicts.

[openjdk]

@phohensee @neethu-prasad Pushed as commit 4c58e1b.

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