[Solved] Error record when using SpringBoot's default asynchronous annotation @Async

Exception description

There is a business that needs to do batch update operations. Each operation will call a change record interface to record the information of the update operation. This interface uses the asynchronous annotation - @Async, and does not specify a thread pool. It is used by default Configuration.

exception information

java.util.concurrent.RejectedExecutionException: Task java.util.concurrent.FutureTask@2665b018[Not completed, task = java.util.concurrent.Executors$RunnableAdapter@63673210[Wrapped task = null]] rejected from java.util.concurrent.ThreadPoolExecutor@1b4a92e[Running, pool size = 10, active threads = 10, queued tasks = 0, completed tasks = 579]
        at java.base/java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(ThreadPoolExecutor.java:2065)
        at java.base/java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:833)
        at java.base/java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1365)
        at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:123)
        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:10327)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10327)
        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:10327)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10327)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10327)
        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:10327)
        at rx.internal.operators.OnSubscribeDefer.call(OnSubscribeDefer.java:51)
        at rx.internal.operators.OnSubscribeDefer.call(OnSubscribeDefer.java:35)
        at rx.Observable.unsafeSubscribe(Observable.java:10327)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
        at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
        at rx.Observable.unsafeSubscribe(Observable.java:10327)
        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:10327)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
        at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
        at rx.Observable.unsafeSubscribe(Observable.java:10327)
        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:10423)
        at rx.Observable.subscribe(Observable.java:10390)
        at rx.internal.operators.BlockingOperatorToFuture.toFuture(BlockingOperatorToFuture.java:51)
        at rx.observables.BlockingObservable.toFuture(BlockingObservable.java:410)
        at com.netflix.hystrix.HystrixCommand.queue(HystrixCommand.java:378)
        at com.netflix.hystrix.HystrixCommand.execute(HystrixCommand.java:344)
        at feign.hystrix.HystrixInvocationHandler.invoke(HystrixInvocationHandler.java:170)
        at jdk.proxy2/jdk.proxy2.$Proxy123.action(Unknown Source)
        at com.tct.relation.service.dataupdate.impl.DataUpdateNoteServiceImpl.qrySomeNameById(DataUpdateNoteServiceImpl.java:631)
        at com.tct.relation.service.dataupdate.impl.DataUpdateNoteServiceImpl.pubSetFieldContents(DataUpdateNoteServiceImpl.java:198)
        at com.tct.relation.service.dataupdate.impl.DataUpdateNoteServiceImpl.addDataUpdateNote(DataUpdateNoteServiceImpl.java:90)
        at com.tct.relation.service.dataupdate.impl.DataUpdateNoteServiceImpl$$FastClassBySpringCGLIB$$ed28d9c8.invoke(<generated>)
        at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218)
        at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:771)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163)
        at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:749)
        at org.springframework.aop.interceptor.AsyncExecutionInterceptor.lambda$invoke$0(AsyncExecutionInterceptor.java:115)
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
        at java.base/java.lang.Thread.run(Thread.java:833)

wrong reason

SpringBoot defaults the default thread pool size of @Async to 8, and the processing strategy when it exceeds is AbortPolicy , which will throw RejectExecutionException, causing program errors to affect the execution results.

Solution

Configure a custom thread pool. When the task exceeds the size of the thread pool, it enters the queue and waits instead of reporting an error. There are many specific ways to configure the thread pool. My configuration is posted below.

package com.tct.relation.config;

import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;

import java.util.concurrent.ThreadPoolExecutor;

/**
 * @author Huhailong
 * @Description 线程池配置
 * @Date 2021/10/9.
 */
@Slf4j
@Configuration
@EnableAsync
public class ThreadPoolTaskConfig {
    
    
    /*
     *   默认情况下，在创建了线程池后，线程池中的线程数为0，当有任务来之后，就会创建一个线程去执行任务，
     *  当线程池中的线程数目达到corePoolSize后，就会把到达的任务放到缓存队列当中；
     *  当队列满了，就继续创建线程，当线程数量大于等于maxPoolSize后，开始使用拒绝策略拒绝
     */

    /**
     * 获得Java虚拟机可用的处理器个数 + 1
     */
    private static final int THREADS = Runtime.getRuntime().availableProcessors() + 1;

    @Value("${async.executor.thread.core_pool_size:0}")
    public static int corePoolSizeConfig;
    // 核心线程池大小
    public static int corePoolSize = corePoolSizeConfig ==0 ? THREADS : corePoolSizeConfig;

    // 最大可创建的线程数
    //@Value("${async.executor.thread.max_pool_size}")
    private final int maxPoolSize = 2 * THREADS;


    //线程池名前缀
    //@Value("${async.executor.thread.threadNamePrefix}")
    private static final String threadNamePrefix = "Async-Service-";

    @Bean(name = "threadPoolTaskExecutor")
    public ThreadPoolTaskExecutor threadPoolTaskExecutor()
    {
    
    
        log.info("core thread count : {}",corePoolSize);
        log.info("max thread pool count : {}",maxPoolSize);
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        executor.setMaxPoolSize(maxPoolSize);
        executor.setCorePoolSize(corePoolSize);
        // 队列最大长度
        //@Value("${async.executor.thread.queue_capacity}")
        int queueCapacity = 1024;
        executor.setQueueCapacity(queueCapacity);
        // 线程池维护线程所允许的空闲时间
        //@Value("${async.executor.thread.keep_alive_seconds}")
        int keepAliveSeconds = 300;
        executor.setKeepAliveSeconds(keepAliveSeconds);
        executor.setThreadNamePrefix(threadNamePrefix);
        // 线程池对拒绝任务(无线程可用)的处理策略
        // CallerRunsPolicy：由调用线程（提交任务的线程）处理该任务
        executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
        // 初始化
        executor.initialize();
        return executor;
    }
}

Change it to @Async("threadPoolTaskExecutor") when using it.
When using something like CompletableFuture, you need to specify a thread pool, which can be ThreadPoolTaskExecutor used through automatic injection.