On Thu, 16 Nov 2023 12:35:08 GMT, Serguei Spitsyn <sspit...@openjdk.org> wrote:
> This is an update for a performance/scalability enhancement. > > The `JvmtiVTMSTransitionDisabler`sync protocol is on a performance critical > path of the virtual threads mount state transitions (VTMS transitions). It > has a noticeable performance overhead (about 10%) which contributes to the > combined JVMTI performance overhead when Java apps are executed with loaded > JVMTI agents. > > Please, also see another/related performance issue which contributes around > 70% of total performance overhead: > [8308614](https://bugs.openjdk.org/browse/JDK-8308614): Enabling JVMTI > ClassLoad event slows down vthread creation by factor 10 > > Testing: > - Ran mach5 tiers 1-6 with no regressions noticed. This pull request has now been integrated. Changeset: 41daa3b9 Author: Serguei Spitsyn <sspit...@openjdk.org> URL: https://git.openjdk.org/jdk/commit/41daa3b934255420dcf414cf9045289ba05a9f48 Stats: 47 lines in 2 files changed: 40 ins; 4 del; 3 mod 8320239: add dynamic switch for JvmtiVTMSTransitionDisabler sync protocol Reviewed-by: lmesnik, pchilanomate, amenkov ------------- PR: https://git.openjdk.org/jdk/pull/16688
