线程池 - java.util.concurrent.RejectedExecutionException

Posted 2023-03-15

【中文标题】线程池 - java.util.concurrent.RejectedExecutionException

【英文标题】：ThreadPool - java.util.concurrent.RejectedExecutionException

【发布时间】：2020-12-21 09:05:53

【问题描述】：

每当我们接到更多电话时，我都会收到 java.util.concurrent.RejectedExecutionException。

我们已将 coreSize 定义为 10，maximumSize 定义为 25，但对于 10 个线程本身，我们会遇到此异常。我们应该在 25 个线程后得到这个异常对吧？我错过了什么吗？你能帮我解决这个问题吗？

hystrix.threadpool.servicename.coreSize=10
hystrix.threadpool.servicename.maximumSize=25

异常跟踪：

java.util.concurrent.RejectedExecutionException: Task java.util.concurrent.FutureTask@74132085 rejected from java.util.concurrent.ThreadPoolExecutor@21e44930[Running, pool size = 10, active threads = 10, queued tasks = 0, completed tasks = 23666917]
at java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(ThreadPoolExecutor.java:2063)
at java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:830)
at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1379)
at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:112)
at com.netflix.hystrix.strategy.concurrency.HystrixContextScheduler$ThreadPoolWorker.schedule(HystrixContextScheduler.java:172)
at com.netflix.hystrix.strategy.concurrency.HystrixContextScheduler$HystrixContextSchedulerWorker.schedule(HystrixContextScheduler.java:106)
at rx.internal.operators.OperatorSubscribeOn.call(OperatorSubscribeOn.java:50)
at rx.internal.operators.OperatorSubscribeOn.call(OperatorSubscribeOn.java:30)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10346)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10346)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10346)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10346)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10346)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10346)
at rx.internal.operators.OnSubscribeDefer.call(OnSubscribeDefer.java:51)
at rx.internal.operators.OnSubscribeDefer.call(OnSubscribeDefer.java:35)
at rx.Observable.unsafeSubscribe(Observable.java:10346)
at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
at rx.Observable.unsafeSubscribe(Observable.java:10346)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10346)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10346)
at rx.internal.operators.OnSubscribeDefer.call(OnSubscribeDefer.java:51)
at rx.internal.operators.OnSubscribeDefer.call(OnSubscribeDefer.java:35)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
at rx.Observable.subscribe(Observable.java:10442)
at rx.Observable.subscribe(Observable

【参考方案1】：

如果你想覆盖maximumSize，你必须设置hystrix.threadpool.default.allowMaximumSizeToDivergeFromCoreSize=true

【参考方案2】：

当线程池无法接受任何新任务时，会发生 RejectedExecutionException。

如果线程池中有空闲线程可用，则立即开始执行任务。否则，任务将在线程池内的queue 中排队。根据线程池的实现，这个队列可能是有界的。在这种情况下，当提交新任务时，由于无法排队，线程池会抛出 RejectedExecutionException。

我不认为你可以在 hystrix 中拥有无限队列。您需要根据 HystrixThreadPoolProperties 中的负载确定适当的队列大小。