On Tue, 30 Apr 2024 01:56:13 GMT, Serguei Spitsyn <sspit...@openjdk.org> wrote:
>> This is a fix of the following JVMTI scalability issue. A closed benchmark >> with millions of virtual threads shows 3X-4X overhead when a JVMTI agent has >> been loaded. For instance, this is observable when an app is executed under >> control of the Oracle Studio `collect` utility. >> For performance analysis, experiments and numbers, please, see the comment >> below this description. >> >> The fix is to replace the global counter `_VTMS_transition_count` with the >> mark bit `_VTMS_transition_mark` in each `JavaThread`'. >> >> Testing: >> - Tested with mach5 tiers 1-6 > > Serguei Spitsyn has updated the pull request incrementally with one > additional commit since the last revision: > > review: correct comments related to VTMS transition counters Marked as reviewed by cjplummer (Reviewer). ------------- PR Review: https://git.openjdk.org/jdk/pull/18937#pullrequestreview-2032369700