On Mon, 5 Oct 2026 16:25:36 GMT, Yunbo Zhang <[email protected]> wrote:
> Please review this small test fix. > > With `-XX:ActiveProcessorCount=1`, `HeapDumpParallelTest` incorrectly expects > serial dumping, even though it configures two GC workers. The heap dump > succeeds, but the test fails because it rejects the parallel dump output. > > **Fix:** > > 1. Identify the target VM's GC from its startup log, including builds that > select Serial GC ergonomically. > 2. Remove the processor-count check, since two workers can perform a parallel > dump even on a single CPU. > 3. Request two threads explicitly for the compressed parallel dump case. > > **Testing:** > > - Passed with G1, Parallel, Serial, Epsilon, ZGC, and Shenandoah, each with > `ActiveProcessorCount=1` and `2`. > - `serviceability/dcmd/gc`: 13 passed, 1 skipped, 0 failed. > > > > --------- > - [x] I confirm that I make this contribution in accordance with the [OpenJDK > Interim AI Policy](https://openjdk.org/legal/ai). Changes requested by lmesnik (Reviewer). test/hotspot/jtreg/serviceability/dcmd/gc/HeapDumpParallelTest.java line 120: > 118: > 119: // Expect parallel dump > 120: test(heapDumpFile, "-gz=9 -overwrite -parallel=2", false); Wouldn't be better to left max(Runtime.getRuntime().availableProcessors(), 2) to use all cores? ------------- PR Review: https://git.openjdk.org/jdk/pull/33212#pullrequestreview-5477399024 PR Review Comment: https://git.openjdk.org/jdk/pull/33212#discussion_r4236253660
