ArrayBlockingQueue vs LinkedBlockingQueue

Feature	ArrayBlockingQueue	LinkedBlockingQueue
Implementation	It’s backed by an array	It uses linked nodes
Queue Size	It’s a bounded queue. Therefore, it’s mandatory to specify the initial capacity while creating it.	It’s not mandatory to mention size.
Fairness Policy	We can set a fairness policy in it	There’s no option to set a fairness policy in this
Number of Locks	It uses one ReentrantLock. The same lock is used for both put and take operations.	It uses separate ReentrantLock for read and write operations. This prevents contention between producer and consumer threads.
Memory space	Since it’s mandatory to mention initial capacity in it, we can end up allocating more space than required.	It usually doesn’t pre-allocate nodes. Therefore, its memory footprint matches its size

알림 서비스 구축시 Thread-Safe한 메시지 큐를 구축하기 위해서 위의 둘중 고민을 하다가 LinkedBlockingQueue를 사용하였다.

 

가장 핵심적인 부분은 네번째 Number of Locks이다.

 

ArrayBlockingQueue는 ReentrantLock을 1개만 사용한다. 즉, ArrayBlockingQueue는 동시에 데이터를 읽거나 사용할 수 없다. 하지만 LinkedBlockingQueue는 동시에 데이터를 읽거나 사용할 수 있다는 큰 차이가 있다.

 

 

참조 : https://www.baeldung.com/java-arrayblockingqueue-vs-linkedblockingqueue