聊聊PowerJob的ThreadPoolConfig

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本文主要研究一下PowerJob的ThreadPoolConfig

ThreadPoolConfig

tech/powerjob/server/config/ThreadPoolConfig.java

@Slf4j
@EnableAsync
@Configuration
public class ThreadPoolConfig {

    @Bean(PJThreadPool.TIMING_POOL)
    public TaskExecutor getTimingPool() {
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        executor.setCorePoolSize(Runtime.getRuntime().availableProcessors());
        executor.setMaxPoolSize(Runtime.getRuntime().availableProcessors() * 4);
        // use SynchronousQueue
        executor.setQueueCapacity(0);
        executor.setKeepAliveSeconds(60);
        executor.setThreadNamePrefix("PJ-TIMING-");
        executor.setRejectedExecutionHandler(new NewThreadRunRejectedExecutionHandler(PJThreadPool.TIMING_POOL));
        return executor;
    }

    @Bean(PJThreadPool.BACKGROUND_POOL)
    public AsyncTaskExecutor initBackgroundPool() {
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        executor.setCorePoolSize(Runtime.getRuntime().availableProcessors() * 8);
        executor.setMaxPoolSize(Runtime.getRuntime().availableProcessors() * 16);
        executor.setQueueCapacity(8192);
        executor.setKeepAliveSeconds(60);
        executor.setThreadNamePrefix("PJ-BG-");
        executor.setRejectedExecutionHandler(RejectedExecutionHandlerFactory.newDiscard(PJThreadPool.BACKGROUND_POOL));
        return executor;
    }

    @Bean(PJThreadPool.LOCAL_DB_POOL)
    public TaskExecutor initOmsLocalDbPool() {
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        int tSize = Math.max(1, Runtime.getRuntime().availableProcessors() / 2);
        executor.setCorePoolSize(tSize);
        executor.setMaxPoolSize(tSize);
        executor.setQueueCapacity(2048);
        executor.setThreadNamePrefix("PJ-LOCALDB-");
        executor.setRejectedExecutionHandler(RejectedExecutionHandlerFactory.newAbort(PJThreadPool.LOCAL_DB_POOL));
        return executor;
    }

    /**
     * 引入 WebSocket 支持后需要手动初始化调度线程池
     */
    @Bean
    public TaskScheduler taskScheduler() {
        ThreadPoolTaskScheduler scheduler = new ThreadPoolTaskScheduler();
        scheduler.setPoolSize(Math.max(Runtime.getRuntime().availableProcessors() * 8, 32));
        scheduler.setThreadNamePrefix("PJ-DEFAULT-");
        scheduler.setDaemon(true);
        return scheduler;
    }

}

ThreadPoolConfig定义了PowerJobTimingPool、PowerJobBackgroundPool、PowerJobLocalDbPool四个线程池，以及一个taskScheduler，这里使用的是spring的ThreadPoolTaskExecutor及ThreadPoolTaskScheduler，他们都继承了ExecutorConfigurationSupport

ExecutorConfigurationSupport

org/springframework/scheduling/concurrent/ExecutorConfigurationSupport.java

public abstract class ExecutorConfigurationSupport extends CustomizableThreadFactory
        implements BeanNameAware, InitializingBean, DisposableBean {

    //......

    /**
     * Calls {@code initialize()} after the container applied all property values.
     * @see #initialize()
     */
    @Override
    public void afterPropertiesSet() {
        initialize();
    }

    /**
     * Set up the ExecutorService.
     */
    public void initialize() {
        if (logger.isDebugEnabled()) {
            logger.debug("Initializing ExecutorService" + (this.beanName != null ? " '" + this.beanName + "'" : ""));
        }
        if (!this.threadNamePrefixSet && this.beanName != null) {
            setThreadNamePrefix(this.beanName + "-");
        }
        this.executor = initializeExecutor(this.threadFactory, this.rejectedExecutionHandler);
    }    

    protected abstract ExecutorService initializeExecutor(
            ThreadFactory threadFactory, RejectedExecutionHandler rejectedExecutionHandler);

    /**
     * Perform a shutdown on the underlying ExecutorService.
     * @see java.util.concurrent.ExecutorService#shutdown()
     * @see java.util.concurrent.ExecutorService#shutdownNow()
     */
    public void shutdown() {
        if (logger.isDebugEnabled()) {
            logger.debug("Shutting down ExecutorService" + (this.beanName != null ? " '" + this.beanName + "'" : ""));
        }
        if (this.executor != null) {
            if (this.waitForTasksToCompleteOnShutdown) {
                this.executor.shutdown();
            }
            else {
                for (Runnable remainingTask : this.executor.shutdownNow()) {
                    cancelRemainingTask(remainingTask);
                }
            }
            awaitTerminationIfNecessary(this.executor);
        }
    }                    
}        

ExecutorConfigurationSupport实现了InitializingBean、DisposableBean接口，在afterPropertiesSet方法执行initialize进行初始化，在destroy方法执行shutdown关闭线程池

小结

ThreadPoolConfig定义了PowerJobTimingPool、PowerJobBackgroundPool、PowerJobLocalDbPool四个线程池，以及一个taskScheduler，这里使用的是spring的ThreadPoolTaskExecutor及ThreadPoolTaskScheduler，他们都继承了ExecutorConfigurationSupport；ExecutorConfigurationSupport实现了InitializingBean、DisposableBean接口，可以自动初始化及销毁线程池。