On Fri, 12 Apr 2024 02:17:34 GMT, Alex Menkov <amen...@openjdk.org> wrote:
> The fix makes VM heap dumping parallel by default. > `jcmd GC.heap_dump` and `jmap -dump` had parallel dumping by default, the fix > affects `HotSpotDiagnosticMXBean.dumpHeap()`, `-XX:+HeapDumpBeforeFullGC`, > `-XX:+HeapDumpAfterFullGC` and `-XX:+HeapDumpOnOutOfMemoryError`. > > Testing: > - manually tested different heap dump scenarios with `-Xlog:heapdump`; > - tier1,tier2,hs-tier5-svc; > - all reg.tests that use heap dump. I am curious: what is the memory overhead for parallel mode, and (I am not familiar with the logic) how many threads are involved? Is the number of thread bounded? I ask because, especially for the OnOOM handling, we may already be at a limit memory-wise. Starting to swap will probably be worse than running single-threaded. ------------- PR Comment: https://git.openjdk.org/jdk/pull/18748#issuecomment-2051046673
