线程池问题记录以及处理

yansq0 / 2023-07-25 / 原文

现象

每天到业务高峰期就会出现提交线程被拒绝。

疑问点

什么原因会导致active threads远远小于poolsize的情况下，提交任务失败

关键信息

线程池配置

ExecutorService aService = new ThreadPoolExecutor(
                130
                , 300
                , 60L
                , TimeUnit.SECONDS
                , new LinkedBlockingQueue<>(10)
                , new ThreadFactoryBuilder().setNameFormat("aService-pool-%d").build()
                , new ThreadPoolExecutor.AbortPolicy()
        );

拒绝任务的日志信息

java.util.concurrent.RejectedExecutionException: Task java.util.concurrent.CompletableFuture$AsyncSupply@4e4dd145 
rejected from java.util.concurrent.ThreadPoolExecutor@5c39c043[Running, pool size = 300, active threads = 4, queued tasks = 8, completed tasks = 3851427]
	at java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(ThreadPoolExecutor.java:2065) ~[?:?]
	at java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:833) ~[?:?]
	at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1365) ~[?:?]
	at java.util.concurrent.CompletableFuture.asyncSupplyStage(CompletableFuture.java:1782) ~[?:?]
	at java.util.concurrent.CompletableFuture.supplyAsync(CompletableFuture.java:2005)

其他信息

这个线程池在使用时存在父子线程都使用的情况，这个用法本身有问题。
从监控来看，java.util.concurrent.ThreadPoolExecutor#getActiveCount 指标最高到40；而 java.util.concurrent.ThreadPoolExecutor#getPoolSize 指标已到高峰期就保持在300