8364503: gc/g1/TestCodeCacheUnloadDuringConcCycle.java fails because of race printing to stdout

[tschatzl]

Hi all,

please review this change to the gc/g1/TestCodeCacheUnloadDuringConcCycle.java test - previously, the GC that we were waiting for in the test could occur between releasing whitebox control and the marker we use to distinguish before/after test setup.

The change makes sure the marker is printed before releasing Whitebox control. So the concurrent start gc we look for can not happen before the marker printing.

Testing: passes 5000 runs of that benchmark

Thanks,
Thomas

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Issue

• JDK-8364503: gc/g1/TestCodeCacheUnloadDuringConcCycle.java fails because of race printing to stdout (Bug - P4)

Reviewers

• Albert Mingkun Yang (@albertnetymk - Reviewer)
• David Holmes (@dholmes-ora - Reviewer)

Reviewing

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[openjdk]

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

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

8364503: gc/g1/TestCodeCacheUnloadDuringConcCycle.java fails because of race printing to stdout

Reviewed-by: ayang, dholmes

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At the time when this comment was updated there had been 55 new commits pushed to the master branch:

• f95af74: 8364312: debug agent should set FD_CLOEXEC flag rather than explicitly closing every open file
• 72d1066: 8364722: Parallel: Move CLDG mark clearing to the end of full GC
• 0ceb366: 8356645: Javac should utilize new ZIP file system read-only access mode
• ... and 52 more: https://git.openjdk.org/jdk/compare/7fbeede14c558221ae0e5b8d65f50e50c0e3737a...master

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• hotspot-gc

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[mlbridge]

Webrevs

• 01: Full - Incremental (3ff76be7)
• 00: Full (fbdc1416)

[dholmes-ora]

Seems reasonable.

I am still curious why this suddenly started showing up.

Thanks

[tschatzl]

Thanks @albertnetymk @dholmes-ora for your reviews
/integrate

[openjdk]

Going to push as commit c56fb0b.
Since your change was applied there have been 58 commits pushed to the master branch:

• 487cc3c: 8359690: New test TestCPUTimeSampleThrottling still fails intermittently
• 078d0d4: 8364235: Fix for JDK-8361447 breaks the alignment requirements for GuardedMemory
• 7e484e2: 8334238: Enhance AddLShortcutTest jpackage test
• ... and 55 more: https://git.openjdk.org/jdk/compare/7fbeede14c558221ae0e5b8d65f50e50c0e3737a...master

Your commit was automatically rebased without conflicts.

[openjdk]

@tschatzl Pushed as commit c56fb0b.

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