Serverless computing is a cloud computing model where the cloud provider dynamically manages the allocation of machine resources. In a traditional server-based model, developers are responsible for provisioning, scaling, and managing servers to run applications. However, in serverless computing, developers focus on writing code (typically in the form of functions or small units of execution) without having to worry about the underlying infrastructure.
Key characteristics of serverless computing include:
1. **Pay-per-use pricing**: With serverless, you’re billed only for the resources consumed during the execution of your code, rather than paying for a fixed amount of server capacity.
2. **Automatic scaling**: The cloud provider automatically scales the resources allocated to your functions based on the incoming request volume. This ensures that your application can handle varying workloads without manual intervention.
3. **Event-driven architecture**: Serverless functions are triggered by events such as HTTP requests, database changes, file uploads, or scheduled tasks. This event-driven model allows for flexible and efficient handling of various types of workloads.
4. **Statelessness**: Serverless functions are typically stateless, meaning they don’t maintain any persistent state between invocations. Any required state must be stored externally, such as in a database or object storage service.
5. **Managed infrastructure**: Cloud providers handle all aspects of infrastructure management, including provisioning, scaling, monitoring, and maintenance. Developers can focus solely on writing code and deploying applications without worrying about server management tasks.
Popular serverless platforms include AWS Lambda, Azure Functions, Google Cloud Functions, and others. Serverless computing is commonly used for building scalable and cost-effective applications, microservices, APIs, event-driven workflows, and real-time data processing systems.
“Hostless” is a term that’s sometimes used to describe certain aspects of serverless computing, particularly in the context of Function as a Service (FaaS) platforms like AWS Lambda, Azure Functions, or Google Cloud Functions. However, it’s not as commonly used as “serverless” itself.
In the serverless paradigm, developers deploy code (often in the form of functions) to a platform, and the platform takes care of managing the underlying infrastructure needed to run that code. This infrastructure management includes provisioning servers, handling scaling, managing networking, and so on. As a result, developers don’t need to worry about the traditional tasks associated with server management.
When we talk about “hostless,” it often refers to the idea that developers are abstracted away from concerns about the underlying hosts or servers that are executing their code. In a traditional server-based model, developers often need to provision specific servers or virtual machines, configure them, and manage their lifecycle. In a hostless or serverless model, this responsibility is shifted to the cloud provider, allowing developers to focus solely on writing code without concerning themselves with the hosting infrastructure.
So, while “hostless” isn’t as commonly used as “serverless,” it essentially emphasizes the idea that developers are freed from dealing with the hosts or servers on which their code runs, thanks to the abstraction provided by serverless platforms.