8257906: JFR: RecordingStream leaks memory

[egahlin]

Hi,

This fix takes care of two memory-leaks that happen when using the RecordingStream in its default configuration.

The first leak happens due to a cache being filled up, but not reset after a chunk segment has been parsed. The second leak is more subtle and happens because objects are created on the heap to track an increased number of chunk files in the disk repository.

Testing: jdk/jdk/jfr

Emitted and parsed about 3 000 chunks and checked the heap usage after GC. A slight increase (10 kb) could be seen over time, resulting in on average 1-2 bytes per million events, but could be due to compressed integers using more space in byte arrays during loading. More time could be spent investigating this, but I like to get these fixes in as soon as possible.

Heap histogram is stable for the important data structures.

Thanks
Erik

---

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Issue

• JDK-8257906: JFR: RecordingStream leaks memory

Reviewers

• Markus Grönlund (@mgronlun - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jdk pull/1774/head:pull/1774
$ git checkout pull/1774

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[mlbridge]

Webrevs

• 00: Full (a9f0916)

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

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8257906: JFR: RecordingStream leaks memory

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At the time when this comment was updated there had been 83 new commits pushed to the master branch:

• da2415f: 8257457: Update --release 16 symbol information for JDK 16 build 28
• 36e2097: 8255917: runtime/cds/SharedBaseAddress.java failed "assert(reserved_rgn != 0LL) failed: No reserved region"
• d53ee62: 8255899: Allow uninstallation of jpackage exe bundles
• 65756ab: 8257802: LogCompilation throws couldn't find bytecode on JDK 8 log
• a372be4: 8258244: Shenandoah: Not expecting forwarded object in roots during mark after JDK-8240868
• 568dc29: 8185734: [Windows] Structured Exception Catcher missing around gtest execution
• 3ab1dfe: 8257828: SafeFetch may crash if invoked in non-JavaThreads
• 381021a: Merge
• afc4441: 8258094: AIX build fails after 8257602
• 164c8a6: 8258092: Link to early access platform documentation in TestHtmlTableTags.java
• ... and 73 more: https://git.openjdk.java.net/jdk/compare/d3dddb6a56776f8179cadf163510b37536e99ac4...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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[egahlin]

/integrate

[openjdk]

@egahlin Since your change was applied there have been 93 commits pushed to the master branch:

• 0c8cc2c: 8258058: improve description of OutOfMemoryError relevant flags
• cdb5342: 8258252: Move PtrQueue enqueue to PtrQueueSet subclasses
• 17ace83: 8258074: Move some flags related to compiler to compiler_globals.hpp
• 47ba652: 8258455: problem list tools/jdeprscan/tests/jdk/jdeprscan/TestRelease.java
• 1e77896: 8236225: Remove expired flags in JDK 17
• 4d6f318: 8257726: Make -XX:+StressLdcRewrite option a diagnostic option
• 8bf46c7: 8258438: build error in test/hotspot/gtest/runtime/test_os.cpp
• 7977e38: 8254024: Enhance native libs for AWT and Swing to work with GraalVM Native Image
• c37eabe: 8252148: vmError::controlled_crash should be #ifdef ASSERT and move tests to gtest
• 2273f95: 8234930: Use MAP_JIT when allocating pages for code cache on macOS
• ... and 83 more: https://git.openjdk.java.net/jdk/compare/d3dddb6a56776f8179cadf163510b37536e99ac4...master

Your commit was automatically rebased without conflicts.

Pushed as commit 3c66485.

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[egahlin]

/backport jdk16

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[egahlin]

/help

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