8258956: Memory Leak in StringCoding on ThreadLocal resultCached StringCoding.Result

[naotoj]

Please review the fix to this issue. Unused thread local StringCoding.Result is now wrapped with SoftReference, which can be GC'ed as needed. I confirmed it worked as expected with a test case (https://github.com/openjdk/jdk/blob/8b4e1e1cf8f5d753ed901406f73d67b21557fddb/test/jdk/java/lang/StringCoding/ResultCachedGCTest.java), but decided not to include it in this PR. This is because I purposefully chose the size of the byte array and max heap size which is fragile, and could become noise in a regression test run.

---

Progress

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Issue

• JDK-8258956: Memory Leak in StringCoding on ThreadLocal resultCached StringCoding.Result

Reviewers

• Roger Riggs (@RogerRiggs - Reviewer)
• Alan Bateman (@AlanBateman - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jdk pull/2064/head:pull/2064
$ git checkout pull/2064

[bridgekeeper]

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[openjdk]

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[mlbridge]

Webrevs

• 00: Full (dee95d3)

[openjdk]

@naotoj 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:

8258956: Memory Leak in StringCoding on ThreadLocal resultCached StringCoding.Result

Reviewed-by: rriggs, alanb

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 26 new commits pushed to the master branch:

• 8b8b1f9: 8259706: C2 compilation fails with assert(vtable_index == Method::invalid_vtable_index) failed: correct sentinel value
• ae9187d: 8256109: Create implementation for NSAccessibilityButton protocol
• 5513f98: 8258010: Debug build failure with clang-10 due to -Wdeprecated-copy
• 51e14f2: Merge
• 5926d75: 8259719: ProblemList runtime/cds/appcds/jigsaw/modulepath/ModulePathAndCP_JFR.java on Windows
• 8abefde: 8259720: ProblemList java/awt/Focus/AppletInitialFocusTest/AppletInitialFocusTest1.java on Windows
• fb8ac24: 8259722: ProblemList two jdk/jfr/startupargs tests on Windows
• ac4cd2e: 8231461: static/instance overload leads to 'unexpected static method found in unbound lookup' when resolving method reference
• 42d2d6d: 8259063: Possible deadlock with vtable/itable creation vs concurrent class unloading
• 6bb6093: 8259657: typo in generated HELP page prevents localization
• ... and 16 more: https://git.openjdk.java.net/jdk/compare/916ab4e7d8aeac010d9ff267a67a9da34017eac3...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.

[naotoj]

/integrate

[openjdk]

@naotoj Since your change was applied there have been 36 commits pushed to the master branch:

• 8554fe6: 8253866: Security Libs Terminology Refresh
• c2a3c7e: 8259727: Remove redundant "target" arguments to methods in Links
• 1620664: 8259723: Move Table class to formats.html package
• 38a1201: 8258912: Remove JVM options CountJNICalls and CountJVMCalls
• be57cf1: 8226416: MonitorUsedDeflationThreshold can cause repeated async deflation requests
• c822eda: 8259699: Reduce char[] copying in URLEncoder.encode(String, Charset)
• ff3e6e4: 8259773: Incorrect encoding of AVX-512 kmovq instruction
• b8ef2ba: 8259563: The CPU model name is printed multiple times when using -Xlog:os+cpu
• b040a3d: 8259631: Reapply pattern match instanceof use in HttpClientImpl
• 3462f7a: 8256955: Move includes of events.hpp out of header files
• ... and 26 more: https://git.openjdk.java.net/jdk/compare/916ab4e7d8aeac010d9ff267a67a9da34017eac3...master

Your commit was automatically rebased without conflicts.

Pushed as commit aba3431.

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