What's Spring's default queue size with a ThreadPoolTaskExecutor?

Question

I\'m using Spring 4.3.8.RELEASE with Java 7. I want to create a thread pool to execute tasks so I have set up the following in my Spring contxet

Answer 1

Be aware of using the default ThreadPoolTaskExecutor if many @Async tasks are executed.

As of Spring Boot 2.1 there is a default ThreadPoolTaskExecutor with a default core size of eight threads. Although the max pool size is still infinity¹ and new threads can be theoretically created the queue size of this pool is infinity¹ as well.

The queue size will probably never hit and new threads will never be created.

At least set the queue size if @Async is used:

spring.task.execution.pool.queue-capacity=16

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¹ infinity as in 2147483647 a.k.a. Integer.MAX_VALUE