On Sun, 17 Apr 2022 16:03:30 GMT, Alan Bateman <al...@openjdk.org> wrote:
>> This is the implementation of JEP 425: Virtual Threads (Preview); TBD which >> JDK version to target. >> >> We will refresh this PR periodically to pick up changes and fixes from the >> loom repo. >> >> Most of the new mechanisms in the HotSpot VM are disabled by default and >> require running with `--enable-preview` to enable. >> >> The patch has support for x64 and aarch64 on the usual operating systems >> (Linux, macOS, and Windows). There are stubs (calling Unimplemented) for >> zero and some of the other ports. Additional ports can be contributed via >> PRs against the fibers branch in the loom repo. >> >> There are changes in many areas. To reduce notifications/mails, the labels >> have been trimmed down for now to hotspot, serviceability and core-libs. >> We'll add the complete set of labels when the PR is further along. >> >> The changes include a refresh of java.util.concurrent and ForkJoinPool from >> Doug Lea's CVS. These changes will probably be proposed and integrated in >> advance of this PR. >> >> The changes include some non-exposed and low-level infrastructure to support >> the (in draft) JEPs for Structured Concurrency and Scope Locals. This is to >> make life a bit easier and avoid having to separate VM changes and juggle >> branches at this time. > > Alan Bateman has updated the pull request incrementally with one additional > commit since the last revision: > > Refresh src/java.management/share/classes/java/lang/management/ThreadMXBean.java line 655: > 653: * synchronization control. It might be an expensive operation. > 654: * Its behavior with cycles involving virtual threads is not defined > 655: * in this release. What does the current implementation return if the virtual threads are involved in a deadlock? The class spec says "ThreadMXBean does not support monitoring or management of virtual threads" while this javadoc says it's undefined. I wonder if it's helpful to include `@implNote` if appropriate. ------------- PR: https://git.openjdk.java.net/jdk/pull/8166