System Design BASICS: Horizontal vs. Vertical Scaling

Summary

This video script introduces the fundamentals of system design, starting with the concept of an algorithm turned into an API accessible over the internet. It covers the transition from a single desktop to cloud computing, explaining the importance of scalability through vertical and horizontal scaling. The script discusses the trade-offs between the two, highlighting the benefits of a hybrid approach that combines speed, consistency, and resilience. It concludes by emphasizing the importance of designing a system that is scalable, resilient, and consistent, acknowledging the inevitable trade-offs in the process.

Takeaways

• 💡 The video is an introduction to system design, aimed at beginners.
• 💻 An algorithm written on a computer can be exposed via an API (Application Programming Interface) for others to use, turning it into a service.
• 🔌 The interaction with the service involves sending a 'request' and receiving a 'response'.
• 🖥️ To support the service, a computer might need to be connected to a database and configured with specific endpoints.
• ⚡ Considerations for system reliability include handling power loss scenarios to ensure continuous service.
• 🌐 Hosting services on the cloud is recommended for scalability and reliability, as it provides access to a set of computers for running algorithms.
• 💨 The cloud is essentially a collection of computers that can be rented for computation power.
• 🔍 Scalability can be achieved through vertical scaling (upgrading to a bigger machine) or horizontal scaling (adding more machines).
• 🔄 Vertical scaling involves a single machine and can be limited by hardware constraints, while horizontal scaling involves multiple machines and can be more resilient.
• 🔗 Network calls between servers in horizontal scaling are slower compared to interprocess communication in vertical scaling.
• 💾 Data consistency can be challenging in horizontally scaled systems due to the complexity of managing transactions across multiple servers.
• 🛠️ A hybrid approach combining the strengths of both vertical and horizontal scaling is often used in real-world systems.

Q & A

What is the purpose of exposing code through an API?

The purpose of exposing code through an API (Application Programming Interface) is to allow users to access and use the code remotely over the internet without needing to physically possess the computer where the code is running. This enables the code to be used by multiple users simultaneously, which can be monetized.

What is the difference between a request and a response in the context of APIs?

In the context of APIs, a request is a message sent to the API to perform a specific action or retrieve data. A response is the result or output that the API sends back after processing the request. Essentially, the request initiates the interaction, and the response concludes it by providing the desired information or result.

Why is it important to consider the need for a database when setting up a computer to run an API?

A database is often necessary when setting up a computer to run an API because it serves as a storage system for the data that the API needs to access or manipulate. This can include user data, application data, or any other relevant information that needs to be retrieved, updated, or managed through the API.

What is the significance of hosting services on the cloud?

Hosting services on the cloud is significant because it provides scalability, reliability, and cost-effectiveness. Cloud services can dynamically adjust to the demand, ensuring that the service remains available even during high traffic. Additionally, cloud providers handle much of the maintenance and security, allowing the focus to be on business requirements rather than infrastructure management.

What is the fundamental difference between a desktop and the cloud in terms of computing?

The fundamental difference between a desktop and the cloud is not in the nature of computing but in the accessibility and management. The cloud is essentially a set of computers provided by a service provider for a fee. These computers can be accessed remotely, similar to a desktop, but they offer the advantage of being scalable and managed by the service provider, reducing the need for local maintenance.

Why is scalability an important consideration in system design?

Scalability is crucial in system design because it determines the system's ability to handle an increasing number of requests as user demand grows. A scalable system can efficiently manage more connections and data, ensuring that the service remains responsive and reliable without degradation in performance.

What are the two main approaches to increasing the scalability of a system?

The two main approaches to increasing the scalability of a system are vertical scaling and horizontal scaling. Vertical scaling involves increasing the capacity of a single machine by making it more powerful, while horizontal scaling involves adding more machines to distribute the workload.

What is the primary advantage of vertical scaling compared to horizontal scaling?

The primary advantage of vertical scaling is that it can provide faster processing due to the increased capacity of a single machine. Additionally, it simplifies data management and ensures data consistency, as all data is stored and processed in one location.

What is the main disadvantage of horizontal scaling in terms of data consistency?

The main disadvantage of horizontal scaling in terms of data consistency is that it can become complex to manage and maintain data integrity across multiple machines. This can lead to issues such as dirty reads or inconsistent data states, requiring more sophisticated mechanisms to ensure transactional integrity.

Why might a system designer choose a hybrid approach combining both vertical and horizontal scaling?

A system designer might choose a hybrid approach to leverage the benefits of both vertical and horizontal scaling. This can provide a balance between the fast processing and data consistency of vertical scaling and the resilience and scalability of horizontal scaling. It allows for efficient resource utilization and better adaptability to varying loads.

What are the key considerations in system design according to the script?

The key considerations in system design, as outlined in the script, are scalability, resilience, and data consistency. Designers must balance these factors to create a system that meets business requirements and can adapt to changing conditions without compromising performance or reliability.