JDK-8287671: Adjust ForceGC to invoke System::gc fewer times for negative case

[mlchung]

This reapplies JDK-8287384 and adjust the number of GCs for negative case, i.e. the condition is never met that is used to verify a reference is not GC'ed.

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Progress

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Issue

• JDK-8287671: Adjust ForceGC to invoke System::gc fewer times for negative case

Reviewers

• Roger Riggs (@RogerRiggs - Reviewer)
• Brent Christian (@bchristi-git - Reviewer)
• Xue-Lei Andrew Fan (@XueleiFan - Reviewer)

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[mlbridge]

Webrevs

• 00: Full (b7307c93)

[openjdk]

@mlchung 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:

8287671: Adjust ForceGC to invoke System::gc fewer times for negative case

Reviewed-by: rriggs, bchristi, xuelei

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At the time when this comment was updated there had been 11 new commits pushed to the master branch:

• 308c068: 8287558: Remove remset coarsening stats during g1 remset summary printing
• d76c108: 8286772: java/awt/dnd/DropTargetInInternalFrameTest/DropTargetInInternalFrameTest.html times out and fails in Windows
• 005a330: 8287826: javax/accessibility/4702233/AccessiblePropertiesTest.java fails to compile
• e2cfe2e: 8231491: JDI tc02x004 failed again due to wrong # of breakpoints
• b6cdfd6: 8287740: NSAccessibilityShowMenuAction not working for text editors
• 25e9901: 8285305: Create an automated test for JDK-4495286
• 6f526e1: 8285373: Create an automated test for JDK-4702233
• a7e07fd: 8287102: ImageReaderSpi.canDecodeInput() for standard plugins should return false if a stream is too short
• 7a0c8b1: 8286850: [macos] Add support for signing user provided app image
• 0b35460: 8283694: Improve bit manipulation and boolean to integer conversion operations on x86_64
• ... and 1 more: https://git.openjdk.java.net/jdk/compare/ce5ae51773974dfc324b5fff52accbe14a0c032e...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this 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.

[XueleiFan]

@mlchung Thank you for pick up and fix the issue.

The waiting time now is reduced from 10 seconds to 1 seconds. As most of the tests intermittent fail, the failure may be more popular now. Alternatively, it might be OK to run less cases in UnloadingTest.java (for example one or two call to tryUnload() in one test by separating the case into a few). But let's see if the intermittent failure is still rare enough.

[mlchung]

JDK-8287384 affects the tests using ForceGC for negative cases only. It will return with a fewer GC cycles of a shortened wait time between each cycle. It will be okay since a strongly reachable reference will never be GC'ed.

[mlchung]

/integrate

[openjdk]

Going to push as commit 2e332c2.
Since your change was applied there have been 22 commits pushed to the master branch:

• c328f8f: 8287764: runtime/cds/serviceability/ReplaceCriticalClasses failed on localized Windows
• 4d6fb51: 8287524: Improve checkboxes to select releases on deprecated API page
• 0d1a305: 8287732: jdk/jshell/ToolEnablePreviewTest.java fails on x86_32 after JDK-8287496
• 24fe8ad: 8283307: Vectorize unsigned shift right on signed subword types
• f347ff9: 8283894: Intrinsify compress and expand bits on x86
• ebc012e: 8287205: generate_cont_thaw generates dead code after jump to exception handler
• 8c460b0: 8287609: macOS: SIGSEGV at [CoreFoundation] CFArrayGetCount / sun.font.CFont.getTableBytesNative
• 3df4b03: 8287837: ProblemList java/lang/ref/OOMEInReferenceHandler.java in -Xcomp
• a6fc485: 8287753: [spelling] close well-established compounds
• a113e16: 8287830: gtest fails to compile after JDK-8287661
• ... and 12 more: https://git.openjdk.java.net/jdk/compare/ce5ae51773974dfc324b5fff52accbe14a0c032e...master

Your commit was automatically rebased without conflicts.

[openjdk]

@mlchung Pushed as commit 2e332c2.

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