On Thu, 29 May 2025 10:15:20 GMT, Alan Bateman <al...@openjdk.org> wrote:
>> Updates the thread dump generated by HotSpotDiagnosticMXBean.dumpThreads and >> jcmd Thread.dump_to_file to include thread state and lock information. Also >> update the HotSpotDiagnosticMXBean.dumpThreads API description to link to a >> description of the JSON format dump as that format is intended to be >> parseable/read by tools. >> >> This PR is dependent on >> [pull/25425](https://github.com/openjdk/jdk/pull/25425). As noted in that >> PR, the changes accumulated in the loom repo, and have been split up to make >> it easier to review. >> >> The changes include some re-implementation of ThreadDumper. This is because >> it used PrintStream and didn't fail if there was an I/O error, e.g. file >> system full. Furthermore, the indentation to pretty print the json was >> fragile and hard to maintain so this is changed to use a supporting writer >> class to do this. >> >> Test coverage is significantly expanded, including updating the test library >> that is used by several tests to parse the thread dump. >> >> Testing: tier1-6 > > Alan Bateman has updated the pull request with a new target base due to a > merge or a rebase. The incremental webrev excludes the unrelated changes > brought in by the merge/rebase. The pull request contains five additional > commits since the last revision: > > - Temp fixed until fixed in pull/25425 > - Sync up from loom repo, includes review comments > - Merge branch 'pull/25425' into JDK-8356870 > - Merge branch 'pull/25425' into JDK-8356870 > - Initial commit src/java.base/share/classes/jdk/internal/vm/ThreadDumper.java line 307: > 305: if (thread.isVirtual()) { > 306: jsonWriter.writeProperty("virtual", Boolean.TRUE); > 307: } Q: Is the order of dumped properties important? The JSON schema lists the `virtual` property after the `state`: 51 "tid": { 52 "type": "string", 53 "description": "The thread identifier." 54 }, 55 "time": { 56 "type": "string", 57 "description": "The time in ISO 8601 format that the thread was sampled." 58 }, 59 "name": { 60 "type": "string", 61 "description": "The thread name." 62 }, 63 "state": { 64 "type": "string", 65 "description": "The thread state (Thread::getState)." 66 }, 67 "virtual" : { 68 "type": "boolean", 69 "description": "true for a virtual thread." 70 }, The other properties dumped in the `dumpThread()` follow the order defined in JSON schema. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/25429#discussion_r2116554217
