December 2022 - 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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Re: RFR: 8280844: Epoch shift synchronization point for Compiler threads is inadequate [v2]
by Markus Grönlund 28 Feb '23

28 Feb '23

> Greetings, > > [JDK-8233111](https://bugs.openjdk.java.net/browse/JDK-8233111) attempted to address artefact tagging for Compiler threads, letting threads run _thread_in_native to avoid the transition. Unfortunately, that attempt proved inadequate. > > The epoch race is avoided only by performing the transition to _thread_in_vm. > > Testing: jdk_jfr > > Thanks > Markus Markus Grönlund has updated the pull request incrementally with one additional commit since the last revision: delegate assertion ------------- Changes: - all: https://git.openjdk.java.net/jdk/pull/8724/files - new: https://git.openjdk.java.net/jdk/pull/8724/files/9ce10130..b4e59b72 Webrevs: - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8724&range=01 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8724&range=00-01 Stats: 3 lines in 1 file changed: 0 ins; 2 del; 1 mod Patch: https://git.openjdk.java.net/jdk/pull/8724.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/8724/head:pull/8724 PR: https://git.openjdk.java.net/jdk/pull/8724

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RFR: 8288783: JFR: Error messages are confusing when options conflict in -XX:StartFlightRecording
by Chihiro Ito 09 Feb '23

09 Feb '23

Could I have a review of PR that fixes incorrect error messages regarding of recording. The current message is very confusing. If a user types jcmd <pid> JFR.start name=abc name=def or java --XX:StartFlightRecording=name=abc,name=def, the error message says "Duplicates in diagnostic command arguments", but doesn't know what options are duplicated. Furthermore, if a user specifies two or three duplicate parameters, the same logs will be output. It should say follows, Option name can only be specified once with starting flight recording Options name and disk can only be specified once with starting flight recording Options name, disk and maxage can only be specified once with starting flight recording This problem affects --XX:StartFlightRecording, jcmd JFR.start, JFR.stop, JFR.dump, JFR.check, and MBean. For other than start, the output is as follows, (example of dump) Option name can only be specified once with dumping flight recording Testing: jdk/jdk/jfr Thanks Chihiro ------------- Commit messages: - modify whitespace from windows to linux - modify copyright - Modify log message and test case - JDK-8288783 Initial Changes: https://git.openjdk.org/jdk/pull/9302/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9302&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8288783 Stats: 442 lines in 10 files changed: 431 ins; 2 del; 9 mod Patch: https://git.openjdk.org/jdk/pull/9302.diff Fetch: git fetch https://git.openjdk.org/jdk pull/9302/head:pull/9302 PR: https://git.openjdk.org/jdk/pull/9302

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RFR: 8298377: JfrVframeStream causes deadlocks in ZGC
by Stefan Karlsson 19 Jan '23

19 Jan '23

The JfrVFrameStream is used while generating stack traces for events. One of the events are the ZPage allocation event. This event is sometimes sent when ZGC is relocating. The current implementation of JfrVFrameStream uses WalkContinuation::include, which causes JFR to walk the continuation and perform GC barriers. This is problematic, since ZGC has a requirement that we never perform load barriers while running the relocation code. If we do, we might end up performing other reloctions from the the relocation code, and in some cases that causes dead locks. I propose that JFR doesn't walk the continuations when sending events. An alternative could be to limit this to ZGC, but I'd like to get some feedback around that from JFR / Loom devs. We've been testing this patch in the Generational ZGC repository. ------------- Commit messages: - 8298377: JfrVframeStream causes deadlocks in ZGC Changes: https://git.openjdk.org/jdk/pull/11586/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11586&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8298377 Stats: 7 lines in 1 file changed: 6 ins; 0 del; 1 mod Patch: https://git.openjdk.org/jdk/pull/11586.diff Fetch: git fetch https://git.openjdk.org/jdk pull/11586/head:pull/11586 PR: https://git.openjdk.org/jdk/pull/11586

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RFR: 8292266: Add JFR event for total Reference processing time
by Sangheon Kim 18 Jan '23

18 Jan '23

Hi all, Can I have reviews for this change that adds a new JFR event for total Reference Processing time? The goal is to generate a new JFR event if there is already measured time. This CR doesn't add new time measurement. Testing: hs-tier1 ~ 3 Thanks, Sangheon ------------- Commit messages: - Remove comment out code. - Combine GCTrace::report method. - Separate GCTrace::report method. Changes: https://git.openjdk.org/jdk/pull/11230/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11230&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8292266 Stats: 141 lines in 11 files changed: 135 ins; 2 del; 4 mod Patch: https://git.openjdk.org/jdk/pull/11230.diff Fetch: git fetch https://git.openjdk.org/jdk pull/11230/head:pull/11230 PR: https://git.openjdk.org/jdk/pull/11230

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RFR: 8299380: conflict assert definitions
by Xue-Lei Andrew Fan 03 Jan '23

03 Jan '23

May I have this code cleanup reviewed? The following failure occurs while building on MacOS M1: In file included from /Users/xueleifan/workspace/jdk-dev/test/hotspot/gtest/jfr/test_networkUtilization.cpp:222: ------------- Commit messages: - update copyright date - 8299380: conflict assert definitions Changes: https://git.openjdk.org/jdk/pull/11792/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11792&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8299380 Stats: 7 lines in 1 file changed: 0 ins; 0 del; 7 mod Patch: https://git.openjdk.org/jdk/pull/11792.diff Fetch: git fetch https://git.openjdk.org/jdk pull/11792/head:pull/11792 PR: https://git.openjdk.org/jdk/pull/11792

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RFR: Merge jdk20
by Jesper Wilhelmsson 25 Dec '22

25 Dec '22

Forwardport JDK 20 -> JDK 21 ------------- Commit messages: - Merge remote-tracking branch 'jdk20/master' into Merge_jdk20 - 8299241: jdk/jfr/api/consumer/streaming/TestJVMCrash.java generates unnecessary core file The merge commit only contains trivial merges, so no merge-specific webrevs have been generated. Changes: https://git.openjdk.org/jdk/pull/11788/files Stats: 8 lines in 2 files changed: 5 ins; 0 del; 3 mod Patch: https://git.openjdk.org/jdk/pull/11788.diff Fetch: git fetch https://git.openjdk.org/jdk pull/11788/head:pull/11788 PR: https://git.openjdk.org/jdk/pull/11788

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RFR: 8298526: Close the stopped jfr after JFR.dump
by xpbob 24 Dec '22

24 Dec '22

start jfr with duration jcmd 31514 JFR.start duration=30s 31514: Started recording 1. Use jcmd 31514 JFR.stop name=1 filename=FILEPATH to copy recording data to file. use JFR.check after 30s jcmd 31514 JFR.check 31514: Recording 1: name=1 duration=30s (stopped) Unable to close the stopped jfr jcmd 31514 JFR.stop name=1 filename=/data/test.jfr 31514: Destination can't be set on a recording that has been stopped/closed ``` Add a check after dump,close the stopped jfr ------------- Commit messages: - 8298526: Close the stopped jfr after JFR.dump Changes: https://git.openjdk.org/jdk/pull/11625/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11625&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8298526 Stats: 4 lines in 1 file changed: 4 ins; 0 del; 0 mod Patch: https://git.openjdk.org/jdk/pull/11625.diff Fetch: git fetch https://git.openjdk.org/jdk pull/11625/head:pull/11625 PR: https://git.openjdk.org/jdk/pull/11625

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[jdk20] RFR: 8299241: jdk/jfr/api/consumer/streaming/TestJVMCrash.java generates unnecessary core file
by Daniel D. Daugherty 23 Dec '22

23 Dec '22

A trivial fix to keep jdk/jfr/api/consumer/streaming/TestJVMCrash.java from generating an unnecessary core file. Ran TestJVMCrash.java on 10 configs in Mach5: linux-aarch64, linux-aarch64-debug, linux-x64, linux-x64-debug, macosx-aarch64, macosx-aarch64-debug, macosx-x64, macosx-x64-debug, windows-x64, and windows-x64-debug. All 10 .jtr files reported: CreateCoredumpOnCrash turned off, no core file dumped Also ran the open ":jdk_jfr" and closed JFR tests on all 10 platforms. No failures. ------------- Commit messages: - 8299241: jdk/jfr/api/consumer/streaming/TestJVMCrash.java generates unnecessary core file Changes: https://git.openjdk.org/jdk20/pull/75/files Webrev: https://webrevs.openjdk.org/?repo=jdk20&pr=75&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8299241 Stats: 8 lines in 2 files changed: 5 ins; 0 del; 3 mod Patch: https://git.openjdk.org/jdk20/pull/75.diff Fetch: git fetch https://git.openjdk.org/jdk20 pull/75/head:pull/75 PR: https://git.openjdk.org/jdk20/pull/75

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RFR: 8298526: JFR: Generate missing filename for time-bound recordings
by Erik Gahlin 20 Dec '22

20 Dec '22

Could I have a review of a change that generates a filename for a recording where a duration has been specified, but no filename has been set. This is most likely what the user wants. This behavior also prevents stopped recordings from hanging around without being closed. For the few users, if any, that want a time-bound recording without a dump file can do filename=/dev/null. Testing: jdk/jdk/jfr Thanks Erik ------------- Commit messages: - Fix comment - Initial Changes: https://git.openjdk.org/jdk/pull/11721/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11721&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8298526 Stats: 38 lines in 2 files changed: 24 ins; 0 del; 14 mod Patch: https://git.openjdk.org/jdk/pull/11721.diff Fetch: git fetch https://git.openjdk.org/jdk pull/11721/head:pull/11721 PR: https://git.openjdk.org/jdk/pull/11721

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