When I was testing executing WildFly workloads on a virtual thread, turning on JVM thread pinning logging (see WFLY-19536) revealed pinning happening in client-side Eclipse Angus code (e.g. sending emails). This issue is to trace working with the Angus community to resolve these issues and get the fixed code into WildFly.
See occurrences of 'onPinned' in https://ci.wildfly.org/repository/download/WF_MainNightlyJobs_StandardLinuxJdk21/446569:id/testsuite/integration/basic/target/wildfly/standalone/log/server.log. Lines in the stack trace annotated with "<== monitor" show where a monitor lock was taken that results in pinning when blocking code executes.
An example:
2024-07-18 05:23:38,520 INFO [stdout] (ForkJoinPool-1-worker-16) Thread[#18608,ForkJoinPool-1-worker-16,5,CarrierThreads] 2024-07-18 05:23:38,520 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/java.lang.VirtualThread$VThreadContinuation.onPinned(VirtualThread.java:185) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/jdk.internal.vm.Continuation.onPinned0(Continuation.java:393) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/java.lang.VirtualThread.park(VirtualThread.java:592) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/java.lang.System$2.parkVirtualThread(System.java:2639) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/jdk.internal.misc.VirtualThreads.park(VirtualThreads.java:54) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/java.util.concurrent.locks.LockSupport.park(LockSupport.java:369) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/sun.nio.ch.Poller$Request.awaitFinish(Poller.java:215) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/sun.nio.ch.Poller.pollIndirect(Poller.java:143) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/sun.nio.ch.Poller.poll(Poller.java:102) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/sun.nio.ch.Poller.poll(Poller.java:89) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/sun.nio.ch.NioSocketImpl.park(NioSocketImpl.java:175) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/sun.nio.ch.NioSocketImpl.park(NioSocketImpl.java:201) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:597) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:327) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/java.net.Socket.connect(Socket.java:751) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) java.base/java.net.Socket.connect(Socket.java:686) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) org.eclipse.angus.mail@2.0.3//org.eclipse.angus.mail.util.SocketFetcher.createSocket(SocketFetcher.java:368) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) org.eclipse.angus.mail@2.0.3//org.eclipse.angus.mail.util.SocketFetcher.getSocket(SocketFetcher.java:243) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) org.eclipse.angus.mail@2.0.3//org.eclipse.angus.mail.pop3.Protocol.<init>(Protocol.java:121) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) org.eclipse.angus.mail@2.0.3//org.eclipse.angus.mail.pop3.POP3Store.getPort(POP3Store.java:250) <== monitors:1 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) org.eclipse.angus.mail@2.0.3//org.eclipse.angus.mail.pop3.POP3Store.protocolConnect(POP3Store.java:192) <== monitors:1 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) jakarta.mail.api@2.1.3//jakarta.mail.Service.connect(Service.java:345) <== monitors:1 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) jakarta.mail.api@2.1.3//jakarta.mail.Service.connect(Service.java:225) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) jakarta.mail.api@2.1.3//jakarta.mail.Service.connect(Service.java:246) 2024-07-18 05:23:38,521 INFO [stdout] (ForkJoinPool-1-worker-16) deployment.d1e69a0b-f63d-4d5f-aa9a-5f42cf984c53.war//org.jboss.as.test.integration.mail.basic.MailTesterServlet.tryToReadEmails(MailTesterServlet.java:73)
Note that in the above stack, jakarta.mail.Service.connect also pins the thread. I'll file a separate issue for that.
To reproduce build https://github.com/bstansberry/wildfly/tree/pinning_check on SE 21.
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WFLY-19563 Support use of virtual threads in the Jakarta Concurrency 3.1. implementation
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- Open
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- is incorporated by
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- Open
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- is related to
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WFLY-19713 Resolve virtual thread pinning issues in client side Jakarta Activation code
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- Open
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- Open
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