8356025: Provide a PrintVMInfoAtExit diagnostic switch

[tstuefe]

Provides a PrintVMInfoAtExit diagnostic switch that, if active, causes the JVM to print out the equivalent of jcmd VM.info before exiting.

The VM.info output contains a large range of valuable information about the JVM and the process.

The switch can be surprisingly useful, e.g. when analysing short-lived processes that are too quick to be analysed with jcmd, or analysing JVM child processes in a process tree, and so on. Going forward, it can also remove the need for some of the more specific PrintxxxAtExit flags.

It can also make writing tests easier (want to make sure switch XX enables condition YY, and YY is printed as part of VM.info? Just start the VM with PrintVMInfoAtExit and parse the output )

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8356025: Provide a PrintVMInfoAtExit diagnostic switch (Enhancement - P4)

Reviewers

• Matthias Baesken (@MBaesken - Reviewer)
• Joel Sikström (@jsikstro - Committer)

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/24980/head:pull/24980
$ git checkout pull/24980

Update a local copy of the PR:
$ git checkout pull/24980
$ git pull https://git.openjdk.org/jdk.git pull/24980/head

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$ git pr checkout 24980

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$ git pr show -t 24980

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https://git.openjdk.org/jdk/pull/24980.diff

Using Webrev

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[bridgekeeper]

👋 Welcome back stuefe! 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]

@tstuefe 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:

8356025: Provide a PrintVMInfoAtExit diagnostic switch

Reviewed-by: mbaesken, jsikstro

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 106 new commits pushed to the master branch:

• ca5e0b1: 8282493: Add --with-jcov-modules convenience option
• a72f750: 8356379: Need a proper way to test existence of binary from configure
• fa765e7: 8356335: Remove linux-x86 from jib profiles
• ... and 103 more: https://git.openjdk.org/jdk/compare/e2ae50d877b13b121912e2496af4b5209b315a05...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]

@tstuefe The following label will be automatically applied to this pull request:

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[mlbridge]

Webrevs

• 02: Full - Incremental (53f5419b)
• 01: Full - Incremental (4445265a)
• 00: Full (88aacea1)

[MBaesken]

Looks like a useful 'thing' , thanks !

[MBaesken]

Not sure why the bits == 64 requirement is there but maybe it is because of the other settings used by the test ?

[tstuefe]

Exactly

[jsikstro]

I really like this. Will be useful when testing and developing printing code.

[tstuefe]

Thanks, folks!

/integrate

[openjdk]

@tstuefe This pull request has not yet been marked as ready for integration.

[jsikstro]

Ah, missed the space in my suggestion.

[tstuefe]

Ah, missed the space in my suggestion.

:-)

Please re-approve (I will wait for tests to run through before integrating)

[tstuefe]

/integrate

[openjdk]

@tstuefe This pull request has not yet been marked as ready for integration.

[tstuefe]

/integrate

[tstuefe]

/integrate

[openjdk]

Going to push as commit da5dc52.
Since your change was applied there have been 109 commits pushed to the master branch:

• c8a30c2: 8347004: vmTestbase/metaspace/shrink_grow/ShrinkGrowTest/ShrinkGrowTest.java fails with CDS disabled
• 90f0f1b: 8354443: [Graal] crash after deopt in TestG1BarrierGeneration.java
• d7e648b: 8355775: Improve symbolic sharing in dynamic constant pool entries
• ... and 106 more: https://git.openjdk.org/jdk/compare/e2ae50d877b13b121912e2496af4b5209b315a05...master

Your commit was automatically rebased without conflicts.

[openjdk]

@tstuefe Pushed as commit da5dc52.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.

[openjdk]

@tstuefe The command integrate can only be used in open pull requests.