On Mon, 15 Apr 2024 23:18:54 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. > > Alex Menkov has updated the pull request incrementally with one additional > commit since the last revision: > > check free_memory for OOME src/hotspot/share/services/heapDumper.hpp line 63: > 61: // additional info is written to out if not null. > 62: // compression >= 0 creates a gzipped file with the given compression > level. > 63: // parallel_thread_num >= 0 indicates thread numbers of parallel object > dump, -1 means "auto select". I don't understand why you need to add `-1` to mean "auto-select" instead of just setting the default parameter to be `default_num_of_dump_threads()`? ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/18748#discussion_r1567017789
