May 2023 - hotspot-jfr-dev

RFR: 8276125: RunThese24H.java SIGSEGV in JfrThreadGroup::thread_group_id
by Markus Grönlund 04 Jun '24

04 Jun '24

Greetings, please help review this changeset. Details are listed in the the JIRA issue. Testing: jdk_jfr Thanks Markus ------------- Commit messages: - 8276125 Changes: https://git.openjdk.java.net/jdk/pull/6702/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=6702&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8276125 Stats: 6 lines in 1 file changed: 4 ins; 0 del; 2 mod Patch: https://git.openjdk.java.net/jdk/pull/6702.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/6702/head:pull/6702 PR: https://git.openjdk.java.net/jdk/pull/6702

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RFR: 8294978: Convert 5 test/jdk/jdk/jfr tests from ASM library to Classfile API
by Chen Liang 03 May '24

03 May '24

Converted these tests to Classfile API and some of the constants to Constant API. InstrumentationCallback.callback wasn't changed to a record since I cannot figure out how to ship a nested record class with InstrumentationCallback in a jar. ------------- Commit messages: - Convert jdk.jfr tests to ASM Changes: https://git.openjdk.org/jdk/pull/13072/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13072&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8294978 Stats: 283 lines in 5 files changed: 75 ins; 108 del; 100 mod Patch: https://git.openjdk.org/jdk/pull/13072.diff Fetch: git fetch https://git.openjdk.org/jdk pull/13072/head:pull/13072 PR: https://git.openjdk.org/jdk/pull/13072

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Re: JFR integration
by Alan Bateman 17 Oct '23

17 Oct '23

On 22/03/2023 17:23, Jonathan Ross wrote: > Hi Alan, and thanks for the response. > > I would agree that naming virtual threads, particularly when using a > VirtualThreadPerTaskExecutor, would not be that useful. No, what I'm > actually asking is whether we could still fill in useful carrier > thread information in the JFR events, and whether we could name the > carrier threads. (I'm using the right term, I hope? The platform > threads on which the virtual threads are run?) > > Let me try to clarify the nameless thread bit. If I look at a flight > recording running a large number of jobs using a > VirtualThreadPerTaskExecutor, then the custom events I record that get > fired on virtual threads don't have any thread information. If I look > at the JMC threadview, I see all my custom events on a single row > without a thread name. If I browse the event list, I also don't see > any thread information. > > I just tried looking at the raw data I captured using the jfr tool > shipped with openjdk 20, but it fails: > > jfr print: unexpected internal error, Pool jdk.types.StackTrace must > contain at least one element > java.lang.InternalError: Pool jdk.types.StackTrace must contain at > least one element > at > jdk.jfr/jdk.jfr.internal.consumer.ChunkParser.fillConstantPools(ChunkParser.java:347) > at > jdk.jfr/jdk.jfr.internal.consumer.ChunkParser.<init>(ChunkParser.java:149) > at > jdk.jfr/jdk.jfr.internal.consumer.ChunkParser.nextChunkParser(ChunkParser.java:158) > at jdk.jfr/jdk.jfr.consumer.RecordingFile.findNext(RecordingFile.java:252) > at > jdk.jfr/jdk.jfr.consumer.RecordingFile.readEvent(RecordingFile.java:111) > at > jdk.jfr/jdk.jfr.internal.tool.EventPrintWriter.print(EventPrintWriter.java:75) > at jdk.jfr/jdk.jfr.internal.tool.Print.execute(Print.java:163) > at jdk.jfr/jdk.jfr.internal.tool.Main.main(Main.java:87) > > It looks like JMC isn't the only tool that gets confused by virtual > threads in flight recordings. > I'm not aware of any issues or if the parsing exception in your mail is related to virtual threads or not, maybe hotspot-jfr-dev may recognize this. As a quick test, I tried some custom events committed from virtual threads and the jfr tool parses the recording, e.g. jfr print --events *Foo* ... Foo { startTime = 17:50:05.595 (2023-03-22) duration = 0.00147 ms message = "A message from a virtual thread" eventThread = "" (javaThreadId = 35, virtual) stackTrace = [ Test.lambda$main$0() line: 21 java.util.concurrent.FutureTask.run() line: 317 java.lang.VirtualThread.run(Runnable) line: 314 ] } Note the eventThread line has the thread name (empty in this case), the thread ID, and it also indicates that it is a virtual thread. -Alan

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RFR: 8307057 JFR: Enable -XX:+DebugNonSafepoints when JFR starts
by Erik Gahlin 16 Sep '23

16 Sep '23

Could I have review of a change that enables DebugNonSafepoints when JFR starts. Testing: tier1, tier2, tier3, tier4 Thanks Erik ------------- Commit messages: - Initial Changes: https://git.openjdk.org/jdk/pull/14147/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14147&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8307057 Stats: 9 lines in 2 files changed: 9 ins; 0 del; 0 mod Patch: https://git.openjdk.org/jdk/pull/14147.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/14147/head:pull/14147 PR: https://git.openjdk.org/jdk/pull/14147

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RFR: 8307488: Incorrect weight of the first ObjectAllocationSample JFR event
by Markus Grönlund 30 May '23

30 May '23

Greetings, this PR fixes the problem with incorrect weights attribution for the initial ObjectAllocationSample event. Testing: jdk_jfr Thanks Markus ------------- Commit messages: - 8307488 Changes: https://git.openjdk.org/jdk/pull/14158/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14158&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8307488 Stats: 81 lines in 4 files changed: 44 ins; 24 del; 13 mod Patch: https://git.openjdk.org/jdk/pull/14158.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/14158/head:pull/14158 PR: https://git.openjdk.org/jdk/pull/14158

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RFR: 8308876 JFR: Deserialization of EventTypeInfo uses incorrect attribute names
by Erik Gahlin 27 May '23

27 May '23

Could I have a review of a bug when deserialzing EventTypeInfo. For details, see CSR. Testing: test/jdk/jdk/jfr Thanks Erik ------------- Commit messages: - Trailing whitespace - Initial Changes: https://git.openjdk.org/jdk/pull/14155/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14155&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8308876 Stats: 19 lines in 2 files changed: 9 ins; 0 del; 10 mod Patch: https://git.openjdk.org/jdk/pull/14155.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/14155/head:pull/14155 PR: https://git.openjdk.org/jdk/pull/14155

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RFR: 8308935: jdk.management.jfr.RecordingInfo.toString() lacks test coverage
by Erik Gahlin 26 May '23

26 May '23

Could I have a review of test fix that adds test coverage for the RecordingInfo.toString() method. Testing: jdk/jdk/jfr/jmx/info/TestRecordingInfo.java Thanks Erik ------------- Commit messages: - Initial Changes: https://git.openjdk.org/jdk/pull/14171/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14171&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8308935 Stats: 16 lines in 1 file changed: 16 ins; 0 del; 0 mod Patch: https://git.openjdk.org/jdk/pull/14171.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/14171/head:pull/14171 PR: https://git.openjdk.org/jdk/pull/14171

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RFR: 8304375: jdk/jfr/api/consumer/filestream/TestOrdered.java failed with "Expected at least some events to be out of order! Reuse = false"
by Erik Gahlin 25 May '23

25 May '23

Could I have a review of a test fix. Not sure why the test fails. The only way I can see is if several events get the exactly the same timestamp. Seems unlikely, but I added a loop to ensure the clock advances on every thread/core and logged the timestamp, so if it fails again, we have more information. Testing: jdk/jfr/api/consumer/filestream/TestOrdered.java Thanks Erik ------------- Commit messages: - Initial Changes: https://git.openjdk.org/jdk/pull/14128/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14128&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8304375 Stats: 6 lines in 1 file changed: 6 ins; 0 del; 0 mod Patch: https://git.openjdk.org/jdk/pull/14128.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/14128/head:pull/14128 PR: https://git.openjdk.org/jdk/pull/14128

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RFR: 8306703: JFR: Summary views
by Erik Gahlin 25 May '23

25 May '23

Could I have a review of an enhancement that adds a view command to jfr. Testing: tier1, tier2 + jdk/jdk/jfr For the change to work properly when streaming, fix of JDK-8306703 needs to be applied. To simplify the review, changes not relevant to the feature, but that can use classes in jdk.jfr.internal.util package, will be refactored after this change has been integrated. Possibly in JDK 22. Thanks Erik ------------- Commit messages: - Initial Changes: https://git.openjdk.org/jdk/pull/14104/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14104&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8306703 Stats: 7516 lines in 65 files changed: 7441 ins; 5 del; 70 mod Patch: https://git.openjdk.org/jdk/pull/14104.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/14104/head:pull/14104 PR: https://git.openjdk.org/jdk/pull/14104

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RFR: 8308335 JFR: Remove @Experimental from Virtual Threads events
by Erik Gahlin 25 May '23

25 May '23

Virtual threads is no longer in preview and experimental annotation should be removed. Testing: test/jdk/jdk/jfr Thanks erik ------------- Commit messages: - Initial Changes: https://git.openjdk.org/jdk/pull/14133/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14133&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8308335 Stats: 18 lines in 5 files changed: 4 ins; 12 del; 2 mod Patch: https://git.openjdk.org/jdk/pull/14133.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/14133/head:pull/14133 PR: https://git.openjdk.org/jdk/pull/14133

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