System Design Notes

What is System Design?

  • System design involves taking a set of requirements and building a product from them.

  • It's a generic term that typically entails deciding on the architecture of a system.

    • Example: Designing the next Facebook requires:

      • A database to store data.

      • API servers to serve requests.

      • CDNs to serve images.

Components and Modules

  • System design includes:

    • Deciding on the architecture.

    • Deciding on the components.

    • Deciding on modules.

  • Example: Facebook design

    • The entire Facebook is the system.

    • Authentication/authorization is a module within Facebook.

    • Web servers, databases, and caches are components within the authentication module.

Flavors of System Design

  • System design comes in three flavors:

    • Designing architecture.

    • Designing components.

    • Designing modules.

  • It's crucial to understand how different parts of the system interact with each other to solve the bigger problem (e.g., building Facebook).

  • Product development life cycle:

    • Decide on architecture.

    • Decide on components.

    • Decide on modules.

Relevance of System Design

  • System design is popular because every tech product is a designed system.

  • Companies need engineers to design these systems.

  • System design is closely related to product development.

  • It involves solving problems using real-world tools like databases, caches, CDNs, servers, compute, encryption, and decryption.

Day-to-Day Relevance

  • System design is very close to what engineers do daily.

  • Upon joining a team, engineers are often presented with design documents explaining the product's architecture.

  • Understanding system design is essential for career growth.

  • As engineers advance to senior roles, they spend a significant amount of time (e.g., 80%) designing systems.

  • The focus shifts to designing the best architecture possible to build the best solution with minimal cost.

Side Effects of System Design

  • System design can make other tasks seem uninteresting due to its engaging nature.

  • Engineers get engrossed in solving problems like authentication or response time optimization.

  • The satisfaction of building a system and seeing users interact with it is rewarding.

  • System design involves solving real problems, unlike some made-up scenarios in data structures and algorithms.

Benefits of System Design

  • System design provides a more relatable experience compared to theoretical concepts.

  • It teaches how to break down a big problem statement into smaller, solvable sub-problems.

  • It rewires the brain to think in a structured way, which helps in various aspects of life.

  • It encourages consideration of all cases, including fault tolerance and availability.

System Design Approach

  • The process involves:

    • Breaking down the problem statement into solvable subproblems.

    • Deciding on key components.

    • Defining the responsibilities of each component.

    • Setting boundaries to avoid overlapping responsibilities.

Key Challenges

  • For every component, consider the key challenges in scaling it.

  • Think intuitively about building scalable systems.

  • Focus on fault tolerance and availability.

  • Consider how the system will recover from the failure of even minor components.

Course Overview

  • The course will cover a lot of theoretical parts in a practical way to build a strong foundation.

  • It will cover a set of interesting systems, each varying differently from the others.

Conclusion

  • The introduction covers the basics of system design.

  • Future videos will use practical examples to understand how systems are built and how to apply first principles to solve problems.