8265489: Stress test times out because of long ObjectSynchronizer::monitors_iterate(...) operation

[lmesnik]

monitors_iterate make several checks which often are true before filter monitor by a thread. It might take a lot of time when there are a lot of threads. So it makes sense to first check thread and only then other conditions.

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Issue

• JDK-8265489: Stress test times out because of long ObjectSynchronizer::monitors_iterate(...) operation

Reviewers

• Daniel D. Daugherty (@dcubed-ojdk - Reviewer)

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[dcubed-ojdk]

The iter is processing the in-use-list and you're bailing the iteration
when you run into an ObjectMonitor that is not owned by thread, but
that doesn't mean that there's not an ObjectMonitor owned by thread
later on in the in-use-list.

So I could see you doing a continue here, but not a return.

[dcubed-ojdk]

Thanks for resolving the above comment.

[mlbridge]

Webrevs

• 00: Full (fdfde75e)

[dcubed-ojdk]

Moving the thread check from the closure's do_monitor() call
into monitors_iterate() as early as possible is a good idea.

Do you have any measurements to show how much this helps?
I'm okay if you don't and I'd be happy waiting to see if it makes
a difference with some of those Tier8 timeouts...

[openjdk]

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

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

8265489: Stress test times out because of long ObjectSynchronizer::monitors_iterate(...) operation

Reviewed-by: dcubed

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At the time when this comment was updated there had been 31 new commits pushed to the master branch:

• ea4907a: 8273047: test jfr/api/consumer/TestRecordedFrame.java timing out
• 4eacdb3: 8273104: Refactoring option parser for UL
• 8884d2f: 8273462: ProblemList vmTestbase/vm/mlvm/anonloader/stress/oome/heap/Test.java in -Xcomp mode
• d6d6c06: 8273246: Amend the test java/nio/channels/DatagramChannel/ManySourcesAndTargets.java to execute in othervm mode
• 708407e: 8273168: Remove superfluous use of boxing in java.desktop
• 270a9d9: 8273043: [TEST_BUG] Automate NimbusJTreeSelTextColor.java
• df05b4d: 8271923: [macos] the text color on the selected disabled tabbed pane button remains white making text unreadable
• 2abf3b3: 8271340: Crash PhaseIdealLoop::clone_outer_loop
• 99fb12c: 8271341: Opcode() != Op_If && Opcode() != Op_RangeCheck) || outcnt() == 2 assert failure with Test7179138_1.java
• 041ae20: 8268558: [TESTBUG] Case 2 in TestP11KeyFactoryGetRSAKeySpec is skipped
• ... and 21 more: https://git.openjdk.java.net/jdk/compare/23fa0dcff062803d249c863b90a00744e3477656...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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[lmesnik]

I run stress tests several times on linux-x64 with ParallelGC and haven't seen timeout anymore.

[lmesnik]

/integrate

[openjdk]

Going to push as commit a5e4def.
Since your change was applied there have been 51 commits pushed to the master branch:

• 9b5991e: 8273451: Remove unreachable return in mutexLocker::wait
• e680503: 8273185: Rename the term "atomic" in ReferenceProcessor
• ba31eee: 8273109: runtime/cds/appcds/loaderConstraints/DynamicLoaderConstraintsTest times out
• 4d5e1ed: 8272375: Improve phrasing of synthesized descriptions in JavaFX docs
• 267c61a: 8273361: InfoOptsTest is failing in tier1
• f7e9f56: 8273359: CI: ciInstanceKlass::get_canonical_holder() doesn't respect instance size
• d7efd0e: 8273450: Fix the copyright header of SVML files
• e5f298a: 8273329: Remove redundant null check from String.getBytes(String charsetName)
• cb112af: 8269373: some tests in jdk/tools/launcher/ fails on localized Windows platform
• 7e662e7: 8272413: Incorrect num of element count calculation for vector cast
• ... and 41 more: https://git.openjdk.java.net/jdk/compare/23fa0dcff062803d249c863b90a00744e3477656...master

Your commit was automatically rebased without conflicts.

[openjdk]

@lmesnik Pushed as commit a5e4def.

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