[ https://issues.apache.org/jira/browse/AMQ-9482?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17847223#comment-17847223 ]
Tom Tichy edited comment on AMQ-9482 at 5/17/24 10:17 AM: ---------------------------------------------------------- Here is a thread dump that I managed to get. ActiveMQ was totally out to lunch and reporting nothing but {code:java} WARN | Transport Connection to: tcp://10.0.88.139:xxxxxx failed: CONNECT frame not received with in connectionTimeout (>30000): tcp://10.0.88.139:xxxxxxx{code} Fastthread.io analyzer came up with this # 'Selector Worker: 12' thread is stuck on *_wait()_* method in *_sun.nio.ch.EPoll_* file. Before getting stuck, this thread obtained *5 locks* (sun.nio.ch.Util$2 lock, sun.nio.ch.EPollSelectorImpl lock...) and never released it. Due to that *4480 threads are* BLOCKED as shown in this [+stack trace+|https://fastthread.io/thread.jsp?tId=MHg0ODMwZQ==&pc=3&dumpId=1&graph=true&ts=2024-05-17T10-07-42]. If threads are BLOCKED for a prolonged period, your application can become unresponsive. Any ideas [~cshannon] ? [^activemq.tdump] was (Author: JIRAUSER305154): Here is a thread dump that I managed to get. ActiveMQ was totally out to lunch and reporting nothing but {code:java} WARN | Transport Connection to: tcp://10.0.88.139:35854 failed: CONNECT frame not received with in connectionTimeout (>30000): tcp://10.0.88.139:35854 {code} Fastthread.io analyzer came up with this # 'Selector Worker: 12' thread is stuck on *_wait()_* method in *_sun.nio.ch.EPoll_* file. Before getting stuck, this thread obtained *5 locks* (sun.nio.ch.Util$2 lock, sun.nio.ch.EPollSelectorImpl lock...) and never released it. Due to that *4480 threads are* BLOCKED as shown in this [+stack trace+|https://fastthread.io/thread.jsp?tId=MHg0ODMwZQ==&pc=3&dumpId=1&graph=true&ts=2024-05-17T10-07-42]. If threads are BLOCKED for a prolonged period, your application can become unresponsive. Any ideas [~cshannon] ? [^activemq.tdump] > Broker crashes after runaway threads spawn > ------------------------------------------ > > Key: AMQ-9482 > URL: https://issues.apache.org/jira/browse/AMQ-9482 > Project: ActiveMQ Classic > Issue Type: Bug > Components: Broker > Affects Versions: 5.17.6, 6.0.1 > Environment: Bitnami created AMI in AWS > Reporter: Tom Tichy > Priority: Major > Attachments: activemq.tdump, brokerInfo-after-crash-redacted.json > > > Running on Bitnami created AMI in AWS. The broker has about 7000 devices > connected via MQTT. Each devices has its own topic name. > Broker stays up for about 4-5 days before being hobbled and unable to create > any new tasks/accept any new connections. > (There is identical setup for staging environment with about 100 devices > connected. It runs without any issues.) > I have troubleshot the cause to be the systemd task limit. The current > `TasksMax` is 18100. When running normally, the number of tasks is about 300. > Then (every 4-5 days) there is a quick spike to the max 18100 tasks and it > stays there never coming back down. The result is that the broker just sits > there, does nothing useful and keeps logging the following message > > {code:java} > [659914.788s][warning][os,thread] Failed to start thread "Unknown thread" - > pthread_create failed (EAGAIN) for attributes: stacksize: 1024k, g > uardsize: 0k, detached. > [659914.788s][warning][os,thread] Failed to start the native thread for > java.lang.Thread "ActiveMQ BrokerService[localhost] Task-281805" > ERROR | Scheduled task error > java.lang.OutOfMemoryError: unable to create native thread: possibly out of > memory or process/resource limits reached > at java.lang.Thread.start0(Native Method) ~[?:?] > at java.lang.Thread.start(Thread.java:809) ~[?:?] > at > java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:945) > ~[?:?] > at > java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1364) > ~[?:?] > at > org.apache.activemq.thread.TaskRunnerFactory.execute(TaskRunnerFactory.java:173) > ~[activemq-client-6.0.1.jar:6.0.1] > at > org.apache.activemq.thread.TaskRunnerFactory.execute(TaskRunnerFactory.java:165) > ~[activemq-client-6.0.1.jar:6.0.1] > at org.apache.activemq.broker.region.Topic$7.run(Topic.java:820) > ~[activemq-broker-6.0.1.jar:6.0.1] > at > org.apache.activemq.thread.SchedulerTimerTask.run(SchedulerTimerTask.java:39) > ~[activemq-client-6.0.1.jar:6.0.1] > at java.util.TimerThread.mainLoop(Timer.java:566) ~[?:?] > at java.util.TimerThread.run(Timer.java:516) ~[?:?] > Exception in thread "ActiveMQ Broker[localhost] Scheduler" > java.lang.OutOfMemoryError: unable to create native thread: possibly out of > memory or process/resource limits reached > at java.base/java.lang.Thread.start0(Native Method) > at java.base/java.lang.Thread.start(Thread.java:809) > at > java.base/java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:945) > at > java.base/java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1364) > at > org.apache.activemq.thread.TaskRunnerFactory.execute(TaskRunnerFactory.java:173) > at > org.apache.activemq.thread.TaskRunnerFactory.execute(TaskRunnerFactory.java:165) > at org.apache.activemq.broker.region.Topic$7.run(Topic.java:820) > at > org.apache.activemq.thread.SchedulerTimerTask.run(SchedulerTimerTask.java:39) > at java.base/java.util.TimerThread.mainLoop(Timer.java:566) > at java.base/java.util.TimerThread.run(Timer.java:516) > {code} > > The start command is > {code:java} > /opt/bitnami/java/bin/java -Xms2G -Xmx4G > -Djava.util.logging.config.file=logging.properties > -Djava.security.auth.login.config=/opt/bitnami/activemq/conf/login.config > -Dorg.apache.activemq.UseDedicatedTaskRunner=false > -Dcom.sun.management.jmxremote -Djava.awt.headless=true > -Djava.io.tmpdir=/opt/bitnami/activemq/tmp --add-reads=java.xml=java.logging > --add-opens java.base/java.security=ALL-UNNAMED --add-opens > java.base/java.net=ALL-UNNAMED --add-opens java.base/java.lang=ALL-UNNAMED > --add-opens java.base/java.util=ALL-UNNAMED --add-opens > java.naming/javax.naming.spi=ALL-UNNAMED --add-opens > java.rmi/sun.rmi.transport.tcp=ALL-UNNAMED --add-opens > java.base/java.util.concurrent=ALL-UNNAMED --add-opens > java.base/java.util.concurrent.atomic=ALL-UNNAMED > --add-exports=java.base/sun.net.www.protocol.http=ALL-UNNAMED > --add-exports=java.base/sun.net.www.protocol.https=ALL-UNNAMED > --add-exports=java.base/sun.net.www.protocol.jar=ALL-UNNAMED > --add-exports=jdk.xml.dom/org.w3c.dom.html=ALL-UNNAMED > --add-exports=jdk.naming.rmi/com.sun.jndi.url.rmi=ALL-UNNAMED > -Dactivemq.classpath=/opt/bitnami/activemq/conf:/opt/bitnami/activemq/../lib/: > -Dactivemq.home=/opt/bitnami/activemq -Dactivemq.base=/opt/bitnami/activemq > -Dactivemq.conf=/opt/bitnami/activemq/conf > -Dactivemq.data=/opt/bitnami/activemq/data > -Djolokia.conf=file:/opt/bitnami/activemq/conf/jolokia-access.xml -jar > /opt/bitnami/activemq/bin/activemq.jar start {code} > During the error condition, I am able to collect broker information via > jolokia: [^brokerInfo-after-crash-redacted.json] > -- This message was sent by Atlassian Jira (v8.20.10#820010)