8330670: Obsolete ScavengeBeforeFullGC

[albertnetymk]

Obsolete a gc product flag.

Test: tier1-3

---

Progress

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• Commit message must refer to an issue
• Change requires CSR request JDK-8330671 to be approved

Issues

• JDK-8330670: Obsolete ScavengeBeforeFullGC (Enhancement - P4)
• JDK-8330671: Obsolete ScavengeBeforeFullGC (CSR)

Reviewers

• Stefan Karlsson (@stefank - Reviewer)
• Thomas Schatzl (@tschatzl - Reviewer)

Reviewing

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Webrev

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[albertnetymk]

/label add hotspot-gc

[bridgekeeper]

👋 Welcome back ayang! 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]

@albertnetymk 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:

8330670: Obsolete ScavengeBeforeFullGC

Reviewed-by: stefank, tschatzl

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 53 new commits pushed to the master branch:

• f60798a: 8329222: java.text.NumberFormat (and subclasses) spec updates
• 2555166: 8329113: Deprecate -XX:+UseNotificationThread
• 09b8809: 8327289: Remove unused PrintMethodFlushingStatistics option
• 9cc163a: 8330178: Clean up non-standard use of /** comments in java.base
• 88a5dce: 8330805: ARM32 build is broken after JDK-8139457
• 7157eea: 8327290: Remove unused notproduct option TraceInvocationCounterOverflow
• b4cea70: 8330693: Generational ZGC: Simplify ZAddress::finalizable_good and ZAddress::mark_good
• 412e306: 8329593: Drop adjustments to target parallelism when virtual threads do I/O on files opened for buffered I/O
• b07e153: 8330362: G1: Inline offset array element accessor in G1BlockOffsetTable
• b6518a5: 8329417: Remove objects with no pointers from relocation bitmap
• ... and 43 more: https://git.openjdk.org/jdk/compare/177092b952c2135c6f6872c6b64d1e210452d35a...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.

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[openjdk]

@albertnetymk
The hotspot-gc label was successfully added.

[mlbridge]

Webrevs

• 00: Full (35c938ea)

[stefank]

I'm not sure if this is correct. We previously returned true here if the user didn't set ScavengeBeforeFullGC, right? Maybe we need a ZGC-specific flag to allow this "precleaning" to be turned off?

[albertnetymk]

ScavengeBeforeFullGC is true by default only for Parallel.

  if (!UseParallelGC && FLAG_IS_DEFAULT(ScavengeBeforeFullGC)) {
    FLAG_SET_DEFAULT(ScavengeBeforeFullGC, false);
  }

[stefank]

Ahh, I missed that. Nowadays we typically put that kind of code in the GC-specific places and not in the shared code.

[albertnetymk]

Thanks for review.

/integrate

[openjdk]

Going to push as commit 7bb59dc.
Since your change was applied there have been 62 commits pushed to the master branch:

• 174d626: 8328741: serviceability/jvmti/ObjectMonitorUsage/ObjectMonitorUsage.java failed with unexpected owner
• e681e9b: 8330819: C2 SuperWord: bad dominance after pre-loop limit adjustment with base that has CastLL after pre-loop
• c439c8c: 8323429: Missing C2 optimization for FP min/max when both inputs are same
• 165ba87: 8330587: IGV: remove ControlFlowTopComponent
• 3ccb64c: 8318446: C2: optimize stores into primitive arrays by combining values into larger store
• 5c38386: 8326541: [AArch64] ZGC C2 load barrier stub should consider the length of live registers when spilling registers
• 438e643: 8329531: compiler/c2/irTests/TestIfMinMax.java fails with IRViolationException: There were one or multiple IR rule failures.
• 80b381e: 8329555: Crash in intrinsifying heap-based MemorySegment Vector store/loads
• 7a89555: 8330844: Add aliases for conditional jumps and additional instruction forms for x86
• f60798a: 8329222: java.text.NumberFormat (and subclasses) spec updates
• ... and 52 more: https://git.openjdk.org/jdk/compare/177092b952c2135c6f6872c6b64d1e210452d35a...master

Your commit was automatically rebased without conflicts.

[openjdk]

@albertnetymk Pushed as commit 7bb59dc.

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