8268893: jcmd to trim the glibc heap

[tstuefe]

Hi,

may I please have reviews for this clean backport of 8268893: "jcmd to trim the glibc heap"?

The command turned out to be very useful to us when analyzing suspected memory leaks. It would be nice to have this in JDK 17.

The associated downport-CSR had been provisionally approved.

The patch applies cleanly.

Thank you, Thomas

---

Progress

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Issue

• JDK-8268893: jcmd to trim the glibc heap

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk17u pull/70/head:pull/70
$ git checkout pull/70

Update a local copy of the PR:
$ git checkout pull/70
$ git pull https://git.openjdk.java.net/jdk17u pull/70/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 70

View PR using the GUI difftool:
$ git pr show -t 70

Using diff file

Download this PR as a diff file:
https://git.openjdk.java.net/jdk17u/pull/70.diff

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8268893: jcmd to trim the glibc heap

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk17u pull/70/head:pull/70
$ git checkout pull/70

Update a local copy of the PR:
$ git checkout pull/70
$ git pull https://git.openjdk.java.net/jdk17u pull/70/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 70

View PR using the GUI difftool:
$ git pr show -t 70

Using diff file

Download this PR as a diff file:
https://git.openjdk.java.net/jdk17u/pull/70.diff

[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]

This backport pull request has now been updated with issue from the original commit.

[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:

8268893: jcmd to trim the glibc heap

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 20 new commits pushed to the master branch:

• 912ae51: 8272342: [TEST_BUG] java/awt/print/PrinterJob/PageDialogMarginTest.java catches all exceptions
• 74de3ef: 8273514: java/util/DoubleStreamSums/CompensatedSums.java failure
• 793d08a: 8214761: Bug in parallel Kahan summation implementation
• cd1d3e0: 8272318: Improve performance of HeapDumpAllTest
• 3a650aa: 8271605: Update JMH devkit to 1.32
• bf788ee: 8271862: C2 intrinsic for Reference.refersTo() is often not used
• 92ff652: 8272970: Parallelize runtime/InvocationTests/
• c2dc88f: 8272850: Drop zapping values in the Zap* option descriptions
• fc8078a: 8263375: Support stack watermarks in Zero VM
• 759cbcb: 8272838: Move CriticalJNI tests out of tier1
• ... and 10 more: https://git.openjdk.java.net/jdk17u/compare/cef269f89633331a68c9549a08d2d88d5534b8fa...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.

[mlbridge]

Webrevs

• 00: Full (0221708c)

[tstuefe]

/integrate

[openjdk]

Going to push as commit d935001.
Since your change was applied there have been 29 commits pushed to the master branch:

• c4dfa57: 8273638: javax/swing/JTable/4235420/bug4235420.java fails in GTK L&F
• 926a815: 8273902: Memory leak in OopStorage due to bug in OopHandle::release()
• d46a5ae: 8274056: JavaAccessibilityUtilities leaks JNI objects
• 7b67581: 8269850: Most JDK releases report macOS version 12 as 10.16 instead of 12.0
• 00f7c45: 8273451: Remove unreachable return in mutexLocker::wait
• 227e159: 8273375: Remove redundant 'new String' calls after concatenation in java.desktop
• 9d590fc: 8261236: C2: ClhsdbJstackXcompStress test fails when StressGCM is enabled
• 8cd9319: 8274215: Remove globalsignr2ca root from 17.0.2
• cb6a08c: 8273646: Add openssl from path variable also in to Default System Openssl Path in OpensslArtifactFetcher
• 912ae51: 8272342: [TEST_BUG] java/awt/print/PrinterJob/PageDialogMarginTest.java catches all exceptions
• ... and 19 more: https://git.openjdk.java.net/jdk17u/compare/cef269f89633331a68c9549a08d2d88d5534b8fa...master

Your commit was automatically rebased without conflicts.

[openjdk]

@tstuefe Pushed as commit d935001.

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