A queue is a data structure or system component that stores items in a first-in, first-out (FIFO) order. In distributed systems, queues decouple producers and consumers, allowing tasks to be processed asynchronously. Queues improve reliability by buffering workloads, smoothing traffic spikes, and enabling retry mechanisms when tasks fail. They are often backed by message brokers or cloud-managed queueing services.
Why it matters
Queues increase system resilience, prevent overload, and support scalable architectures. They are essential in event-driven systems, background job processing, and microservices communication. Without queues, services must coordinate synchronously, reducing fault tolerance and performance.
Examples
Using Amazon SQS to queue background tasks or RabbitMQ to distribute messages between microservices. Lessons like Background Jobs and Queues illustrate queue workflows.