> 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.
Serguei Spitsyn has updated the pull request incrementally with one additional commit since the last revision: review: make new fields volatile, use Atomic for access/update ------------- Changes: - all: https://git.openjdk.org/jdk/pull/16688/files - new: https://git.openjdk.org/jdk/pull/16688/files/bf093127..a81218fd Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=16688&range=01 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=16688&range=00-01 Stats: 15 lines in 2 files changed: 3 ins; 0 del; 12 mod Patch: https://git.openjdk.org/jdk/pull/16688.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/16688/head:pull/16688 PR: https://git.openjdk.org/jdk/pull/16688
