April 2025 - hotspot-jfr-dev

Re: RFR: 8352251: Implement Cooperative JFR Sampling [v9]
by Markus Grönlund 23 Apr '25

23 Apr '25

> Greetings, > > This is the implementation of JEP [JDK-8350338 Cooperative JFR Sampling](https://bugs.openjdk.org/browse/JDK-8350338). > > Implementations in this change set are provided and have been tested on the following platforms: > > - windows-x64 > - windows-x64-debug > - linux-x64 > - linux-x64-debug > - macosx-x64 > - macosx-x64-debug > - linux-aarch64 > - linux-aarch64-debug > - macosx-aarch64 > - macosx-aarch64-debug > > Testing: tier1-6, jdk_jfr, stress testing. > > Platform porters note: > Some platform-specific code needs to be provided, mainly in the interpreter. Take a look at the following files for changes: > > - src/hotspot/cpu/x86/frame_x86.cpp > - src/hotspot/cpu/x86/interp_masm_x86.cpp > - src/hotspot/cpu/x86/interp_masm_x86.hpp > - src/hotspot/cpu/x86/javaFrameAnchor_x86.hpp > - src/hotspot/cpu/x86/macroAssembler_x86.cpp > - src/hotspot/cpu/x86/macroAssembler_x86.hpp > - src/hotspot/cpu/x86/templateInterpreterGenerator_x86.cpp > - src/hotspot/cpu/x86/templateTable_x86.cpp > - src/hotspot/os_cpu/linux_x86/javaThread_linux_x86.hpp > > Thanks > Markus Markus Grönlund has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 12 commits: - Merge branch 'master' into 8352251 - Refine SamplingLatency event description - Update default.jfc - Update profile.jfc - review comments - Merge branch '8352251' of github.com:mgronlun/jdk into 8352251 - Merge branch 'master' into 8352251 - Merge branch 'master' into 8352251 - align params - adjustments - ... and 2 more: https://git.openjdk.org/jdk/compare/d61765f6...5f2351c8 ------------- Changes: https://git.openjdk.org/jdk/pull/24296/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24296&range=08 Stats: 3212 lines in 77 files changed: 1906 ins; 960 del; 346 mod Patch: https://git.openjdk.org/jdk/pull/24296.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/24296/head:pull/24296 PR: https://git.openjdk.org/jdk/pull/24296

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RFR: 8354949: JFR: Split up the EventInstrumentation class
by Erik Gahlin 23 Apr '25

23 Apr '25

Could I have a review of a PR that cleans up the EventInstrumentation class and moves the non-modifying parts into a separate class (ClassInspector)? I deleted the code that removes the instrumentation (buildUninstrumented), because it has never been used. If there should be a need for it in the future, it's not hard to add code that inserts empty method bodies. Testing: tier1 + jdk/jdk/jfr/test Thanks Erik ------------- Commit messages: - Initial Changes: https://git.openjdk.org/jdk/pull/24726/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24726&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8354949 Stats: 977 lines in 5 files changed: 448 ins; 359 del; 170 mod Patch: https://git.openjdk.org/jdk/pull/24726.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/24726/head:pull/24726 PR: https://git.openjdk.org/jdk/pull/24726

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Re: RFR: 8352251: Implement Cooperative JFR Sampling [v8]
by Markus Grönlund 21 Apr '25

21 Apr '25

> Greetings, > > This is the implementation of JEP [JDK-8350338 Cooperative JFR Sampling](https://bugs.openjdk.org/browse/JDK-8350338). > > Implementations in this change set are provided and have been tested on the following platforms: > > - windows-x64 > - windows-x64-debug > - linux-x64 > - linux-x64-debug > - macosx-x64 > - macosx-x64-debug > - linux-aarch64 > - linux-aarch64-debug > - macosx-aarch64 > - macosx-aarch64-debug > > Testing: tier1-6, jdk_jfr, stress testing. > > Platform porters note: > Some platform-specific code needs to be provided, mainly in the interpreter. Take a look at the following files for changes: > > - src/hotspot/cpu/x86/frame_x86.cpp > - src/hotspot/cpu/x86/interp_masm_x86.cpp > - src/hotspot/cpu/x86/interp_masm_x86.hpp > - src/hotspot/cpu/x86/javaFrameAnchor_x86.hpp > - src/hotspot/cpu/x86/macroAssembler_x86.cpp > - src/hotspot/cpu/x86/macroAssembler_x86.hpp > - src/hotspot/cpu/x86/templateInterpreterGenerator_x86.cpp > - src/hotspot/cpu/x86/templateTable_x86.cpp > - src/hotspot/os_cpu/linux_x86/javaThread_linux_x86.hpp > > Thanks > Markus Markus Grönlund has updated the pull request incrementally with one additional commit since the last revision: Refine SamplingLatency event description ------------- Changes: - all: https://git.openjdk.org/jdk/pull/24296/files - new: https://git.openjdk.org/jdk/pull/24296/files/d6854a84..447ce857 Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=24296&range=07 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24296&range=06-07 Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod Patch: https://git.openjdk.org/jdk/pull/24296.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/24296/head:pull/24296 PR: https://git.openjdk.org/jdk/pull/24296

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Re: RFR: 8352251: Implement Cooperative JFR Sampling [v7]
by Markus Grönlund 21 Apr '25

21 Apr '25

> Greetings, > > This is the implementation of JEP [JDK-8350338 Cooperative JFR Sampling](https://bugs.openjdk.org/browse/JDK-8350338). > > Implementations in this change set are provided and have been tested on the following platforms: > > - windows-x64 > - windows-x64-debug > - linux-x64 > - linux-x64-debug > - macosx-x64 > - macosx-x64-debug > - linux-aarch64 > - linux-aarch64-debug > - macosx-aarch64 > - macosx-aarch64-debug > > Testing: tier1-6, jdk_jfr, stress testing. > > Platform porters note: > Some platform-specific code needs to be provided, mainly in the interpreter. Take a look at the following files for changes: > > - src/hotspot/cpu/x86/frame_x86.cpp > - src/hotspot/cpu/x86/interp_masm_x86.cpp > - src/hotspot/cpu/x86/interp_masm_x86.hpp > - src/hotspot/cpu/x86/javaFrameAnchor_x86.hpp > - src/hotspot/cpu/x86/macroAssembler_x86.cpp > - src/hotspot/cpu/x86/macroAssembler_x86.hpp > - src/hotspot/cpu/x86/templateInterpreterGenerator_x86.cpp > - src/hotspot/cpu/x86/templateTable_x86.cpp > - src/hotspot/os_cpu/linux_x86/javaThread_linux_x86.hpp > > Thanks > Markus Markus Grönlund has updated the pull request incrementally with two additional commits since the last revision: - Update default.jfc - Update profile.jfc ------------- Changes: - all: https://git.openjdk.org/jdk/pull/24296/files - new: https://git.openjdk.org/jdk/pull/24296/files/0da2c2d9..d6854a84 Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=24296&range=06 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24296&range=05-06 Stats: 3 lines in 2 files changed: 2 ins; 0 del; 1 mod Patch: https://git.openjdk.org/jdk/pull/24296.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/24296/head:pull/24296 PR: https://git.openjdk.org/jdk/pull/24296

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Re: RFR: 8352251: Implement Cooperative JFR Sampling [v6]
by Markus Grönlund 19 Apr '25

19 Apr '25

> Greetings, > > This is the implementation of JEP [JDK-8350338 Cooperative JFR Sampling](https://bugs.openjdk.org/browse/JDK-8350338). > > Implementations in this change set are provided and have been tested on the following platforms: > > - windows-x64 > - windows-x64-debug > - linux-x64 > - linux-x64-debug > - macosx-x64 > - macosx-x64-debug > - linux-aarch64 > - linux-aarch64-debug > - macosx-aarch64 > - macosx-aarch64-debug > > Testing: tier1-6, jdk_jfr, stress testing. > > Platform porters note: > Some platform-specific code needs to be provided, mainly in the interpreter. Take a look at the following files for changes: > > - src/hotspot/cpu/x86/frame_x86.cpp > - src/hotspot/cpu/x86/interp_masm_x86.cpp > - src/hotspot/cpu/x86/interp_masm_x86.hpp > - src/hotspot/cpu/x86/javaFrameAnchor_x86.hpp > - src/hotspot/cpu/x86/macroAssembler_x86.cpp > - src/hotspot/cpu/x86/macroAssembler_x86.hpp > - src/hotspot/cpu/x86/templateInterpreterGenerator_x86.cpp > - src/hotspot/cpu/x86/templateTable_x86.cpp > - src/hotspot/os_cpu/linux_x86/javaThread_linux_x86.hpp > > Thanks > Markus Markus Grönlund has updated the pull request incrementally with one additional commit since the last revision: review comments ------------- Changes: - all: https://git.openjdk.org/jdk/pull/24296/files - new: https://git.openjdk.org/jdk/pull/24296/files/e48905fc..0da2c2d9 Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=24296&range=05 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24296&range=04-05 Stats: 4 lines in 3 files changed: 0 ins; 0 del; 4 mod Patch: https://git.openjdk.org/jdk/pull/24296.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/24296/head:pull/24296 PR: https://git.openjdk.org/jdk/pull/24296

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Re: RFR: 8352251: Implement Cooperative JFR Sampling [v5]
by Markus Grönlund 18 Apr '25

18 Apr '25

> Greetings, > > This is the implementation of JEP [JDK-8350338 Cooperative JFR Sampling](https://bugs.openjdk.org/browse/JDK-8350338). > > Implementations in this change set are provided and have been tested on the following platforms: > > - windows-x64 > - windows-x64-debug > - linux-x64 > - linux-x64-debug > - macosx-x64 > - macosx-x64-debug > - linux-aarch64 > - linux-aarch64-debug > - macosx-aarch64 > - macosx-aarch64-debug > > Testing: tier1-6, jdk_jfr, stress testing. > > Platform porters note: > Some platform-specific code needs to be provided, mainly in the interpreter. Take a look at the following files for changes: > > - src/hotspot/cpu/x86/frame_x86.cpp > - src/hotspot/cpu/x86/interp_masm_x86.cpp > - src/hotspot/cpu/x86/interp_masm_x86.hpp > - src/hotspot/cpu/x86/javaFrameAnchor_x86.hpp > - src/hotspot/cpu/x86/macroAssembler_x86.cpp > - src/hotspot/cpu/x86/macroAssembler_x86.hpp > - src/hotspot/cpu/x86/templateInterpreterGenerator_x86.cpp > - src/hotspot/cpu/x86/templateTable_x86.cpp > - src/hotspot/os_cpu/linux_x86/javaThread_linux_x86.hpp > > Thanks > Markus Markus Grönlund has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains seven commits: - Merge branch '8352251' of github.com:mgronlun/jdk into 8352251 - Merge branch 'master' into 8352251 - Merge branch 'master' into 8352251 - align params - adjustments - refactoring - 8352251 ------------- Changes: https://git.openjdk.org/jdk/pull/24296/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24296&range=04 Stats: 3211 lines in 77 files changed: 1904 ins; 960 del; 347 mod Patch: https://git.openjdk.org/jdk/pull/24296.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/24296/head:pull/24296 PR: https://git.openjdk.org/jdk/pull/24296

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RFR: 8295651: JFR: 'jfr scrub' should summarize what was removed
by Erik Gahlin 16 Apr '25

16 Apr '25

Could I have a review of an enhancement that summarizes the results of `jfr scrub`? To accommodate this feature, I made some additional changes: - Added a LongMap::values() method. - Added a Command::printf(...) method, which is now also used by `jfr summary`. - Improved TestScrub.java so it now creates a file that spans multiple chunks, including an empty one. See issue for example output. Testing: jdk/jdk/jfr Thanks Erik ------------- Commit messages: - Only collect if 'jfr scrub' is used - Initial Changes: https://git.openjdk.org/jdk/pull/24669/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24669&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8295651 Stats: 138 lines in 9 files changed: 123 ins; 2 del; 13 mod Patch: https://git.openjdk.org/jdk/pull/24669.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/24669/head:pull/24669 PR: https://git.openjdk.org/jdk/pull/24669

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RFR: 8352942: jdk/jfr/startupargs/TestMemoryOptions.java fails with 32-bit build
by KIRIYAMA Takuya 16 Apr '25

16 Apr '25

Hi All, I would like to add this bug fix for the bug in jdk/jfr/startupargs/TestMemoryOptions.java. I was unable to reproduce the reported problem in java versions 11 and later. Therefore, I made a pull request for 8u before. https://github.com/openjdk/jdk8u-dev/pull/641 However, the latest java should be fixed, as the bugs described below will potentially remain in the test. This test contains 24 test cases and fails the "ThreadBufferSizeExceedMemorySize" case. The cause of this bug is the memory allocation issue, which occurs only on 32-bit Server VM, not on Client VM or 64-bit JDK. The failure happens because Server VM's default heap size reduces available memory space, causing JFR to fail memory allocation. To resolve this issue, -Xmx256M is explicitly set, matching the Client VM default heap size, ensuring sufficient memory space remains available for JFR. I believe that this test verifies that the combination of memory options for JFR is valid or invalid and that the MaxHeapSize setting does not affect the verification. Change has been verified locally, test-fix only, no risk. Would someone please review this fix? ------------- Commit messages: - 8352942: jdk/jfr/startupargs/TestMemoryOptions.java fails with 32-bit build Changes: https://git.openjdk.org/jdk/pull/24646/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24646&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8352942 Stats: 2 lines in 1 file changed: 2 ins; 0 del; 0 mod Patch: https://git.openjdk.org/jdk/pull/24646.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/24646/head:pull/24646 PR: https://git.openjdk.org/jdk/pull/24646

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New candidate JEP: 509: JFR CPU-Time Profiling (Experimental)
by Mark Reinhold 15 Apr '25

15 Apr '25

https://openjdk.org/jeps/509 Summary: Enhance the JDK Flight Recorder (JFR) to capture CPU-time profiling information on Linux. This is an experimental feature. - Mark

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RFR: 8354508: JFR: Strengthen metadata checks for labels
by Erik Gahlin 15 Apr '25

15 Apr '25

Could I have a review of a PR that improves the checks for label metadata? When running TestEventMetadata, I found some fields with incorrect capitalization. I fixed those, as well as some typos, and updated the filename from trace.xml to metadata.xml. Testing: jdk/jdk/jfr Thanks Erik ------------- Commit messages: - Fixes - Initial Changes: https://git.openjdk.org/jdk/pull/24616/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24616&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8354508 Stats: 77 lines in 2 files changed: 46 ins; 5 del; 26 mod Patch: https://git.openjdk.org/jdk/pull/24616.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/24616/head:pull/24616 PR: https://git.openjdk.org/jdk/pull/24616

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