What are the mechanisms of queue caching?

Queue caching mechanisms include first-in-first-out, first-in-last-out, priority queue, etc. Detailed introduction: 1. First in, first out (FIFO): The earliest element in the queue is deleted first. When new elements enter the queue, they are added to the end of the queue. When the queue is not full, new elements can be added to the queue; when the queue is full, new elements cannot be added to the queue and need to wait for elements in the queue to be removed before they can enter; 2. First in, last out (LIFO) ): The last element entered in the queue is the last one to be deleted, etc.

Operating system for this tutorial: Windows 10 system, Dell G3 computer.

The mechanisms of queue caching mainly include the following:

1. First in, first out (FIFO): The earliest element in the queue is deleted first. When new elements enter the queue, they are added to the end of the queue. When the queue is not full, new elements can be added to the queue; when the queue is full, new elements cannot be added to the queue and must wait for elements in the queue to be removed before they can enter.
2. First in, last out (LIFO): The last element entered in the queue is the last to be deleted. When new elements enter the queue, they are added to the top of the queue. When the queue is not full, new elements can be added to the queue; when the queue is full, new elements cannot be added to the queue and must wait for elements in the queue to be removed before they can enter.
3. Priority queue: In a priority queue, the priority of elements determines the order in which they are deleted. High-priority elements are deleted before low-priority elements. When new elements enter the queue, they are assigned a priority. When the queue is not full, new elements can be added to the queue; when the queue is full, new elements cannot be added to the queue and must wait for elements in the queue to be removed before they can enter.

Queue caching mechanism is usually used to cache and process tasks or messages in multi-threaded or distributed systems. By using the queue caching mechanism, you can avoid concurrency control and performance problems caused by operations such as direct access to shared resources or databases. At the same time, the queue caching mechanism can also provide a certain message persistence mechanism so that previously unprocessed tasks or messages can be restored after a system crash or restart.

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