Serverless vs. Microservices: 4 Differences and Potential Synergies

What Is Serverless? 

Serverless is an innovative approach to application development that enables developers to build and run applications without having to manage the underlying infrastructure. In a serverless environment, the cloud provider takes care of provisioning, scaling, and managing the servers required to run the application, allowing developers to focus on writing code.

Key benefits of serverless include:

• Flexibility and scalability: With serverless, you can easily adjust the resources allocated to your application in response to changes in demand. This means that as your application grows and evolves, you can quickly and seamlessly scale your infrastructure to meet the demands of your users.
• Cost efficiency: In a serverless environment, you only pay for the compute resources you actually use, rather than paying for pre-allocated resources. This can result in significant cost savings, particularly for applications with variable workloads or unpredictable usage patterns.
• Faster time to market: By removing the need to manage infrastructure, serverless allows developers to focus on writing code and delivering new features more quickly. This can lead to a faster time to market for your application.

This is part of a series of articles about serverless monitoring

What Are Microservices? 

Microservices is an architectural style that structures an application as a collection of small, loosely coupled services. Each service is responsible for a specific piece of functionality and can be developed, deployed, and scaled independently. This approach enables organizations to build and maintain large-scale applications more efficiently by breaking them down into smaller, manageable components.

Key benefits of microservices include:

• Independent development and deployment: One of the main advantages of microservices is the ability to develop and deploy each service independently. This allows teams to work on different parts of the application simultaneously, reducing the time and effort required to deliver new features and updates.
• Fault isolation: Another benefit of microservices is improved fault isolation. With a monolithic application, a failure in one component can cause the entire application to crash. In contrast, microservices allow for better fault isolation, as a failure in one service is less likely to affect the rest of the application.

Easier scaling: Microservices make it easier to scale your application, as you can independently scale each service based on its specific needs. This is particularly useful for applications with varying workloads and usage patterns, as it allows you to optimize resource allocation for each service.

Serverless vs. Microservices: 4 Key Differences 

Before we explore the differences between serverless and microservices, it’s important to understand that they are not mutually exclusive. It is quite common to run some microservices as serverless functions. However, in this comparison, we’ll compare a full microservices application with a minimal approach based only on serverless functions.

1. Complex Applications vs. Short-Term Services

The serverless and microservices model have different strategies at their core. Microservices are designed for applications that need to run in the long term. They provide persistence and high scalability for complex applications.

The serverless model is designed for efficiency. Unlike microservices that run continuously, serverless functions only run in response to specific triggers or inputs. The serverless architecture is event-induced, meaning in the absence of a trigger, no function is performed. This eliminates unnecessary CPU usage, saving costs and reducing overheads.

2. Responsibility for Maintenance

Microservices are dependent on the capabilities of the development team, whether in-house or outsourced. This team manages monitoring, deployment, support, and maintenance. All aspects regarding the architecture’s support, computing, and security are the team’s responsibility.

Serverless, on the other hand, relies on a third-party provider. The development team does not need to deploy and maintain server infrastructure. All internal procedures are managed by the cloud vendor. This strategy helps cut project costs, avoid recruitment and training expenses, as well as hardware investments and storage costs.

3. Costs

The initial stages of developing microservices are costly. The project requires several teams to develop each component and merge them via APIs. Since microservices leverage in-house resources and support, their development and upkeep tend to be pricey. However, there are benefits to this approach such as independence from third-party plans and avoiding potential vendor lock-in.

Conversely, a serverless architecture generally enables lower costs. Developers only need to write specific code elements, which are automatically deployed by the serverless runtime. There is no need for server and hardware specialists and overall development complexity is reduced.

4. Runtime Considerations

Serverless functions have a restricted runtime. Each provider sets its own limit on the duration a function can run. For instance, on AWS Lambda, a function is limited to run for 15 minutes. This is because by design, functions are short-term processes intended to minimize RAM usage.

Microservices are not bound by vendor restrictions on runtime, storage capacity, and RAM. This makes them ideal for intricate long-term tasks that necessitate handling and manipulation of immense data amounts.

Related content: Read our guide to serverless logging

Adding Serverless to Your Microservices Applications 

In reality, most development teams don’t need to choose between serverless and microservice architectures. Major Cloud providers (Google, Amazon, Microsoft) have recognized the rising demand for these methodologies and can support both full-fledged microservices applications and lightweight serverless applications. Microservices can be engineered as a combination of containers, event-driven serverless functions, or using other deployment models.

Here are key considerations for development teams aiming to integrate serverless more deeply into their microservices applications:

1. Cloud deployment: Embracing the cloud is an essential part of serverless, because serverless development leans heavily on third-party cloud services. In order to adopt serverless as part of your microservices application, consider moving your application to cloud-based infrastructure.
2. Event-driven focus: Microservices should be deployed as serverless functions if they are triggered by events. For a microservice to function as a serverless operation, it should react to specific conditions and user actions.
3. Orchestration: Developers can better manage serverless functions by orchestrating them, using tools like Microsoft Logic Apps or Amazon Step Functions. These tools allow assigning of triggers to microservices and combining multiple serverless functions into a bigger service.

Related content: Read our guide to serverless observability

Monitoring Serverless Applications and Microservices with Lumigo

Lumigo is a troubleshooting platform, purpose-built for microservice-based applications. Developers using container technologies like Kubernetes or serverless services like AWS Lambda, to orchestrate their applications can use Lumigo to monitor, trace and troubleshoot issues fast. Deployed with zero-code changes and automated in one-click, Lumigo stitches together every interaction between micro and managed service into end-to-end stack traces. These traces, served alongside request payload data, give developers complete visibility into their container environments. Using Lumigo, developers get:

• End-to-end virtual stack traces across every micro and managed service that makes up a serverless application, in context
• API visibility that makes all the data passed between services available and accessible, making it possible to perform root cause analysis without digging through logs
• Distributed tracing that is deployed with no code and automated in one click
• Unified platform to explore and query across microservices, see a real-time view of applications, and optimize performance

Get started with a free trial of Lumigo for your microservice applications.