System Design

Must consider some tradeoffs when designing a system.

This is the first part when starting a project, because this is where you will pick which tools, definitions, architechtures will be used to develop and serve the product/idea.

Tradeoffs to think about

Some of the tradeoffs to be thought and considered.

Scalability vs Complexity

• Raising scalability usually add more complexity.

  • Like using load balancing, horizontal scaling...

Consistency vs Availability (CAP theorem)

• In distributed systems, CAP Theorem says that it is impossible to garantee Consistency, Availability and Partition Tolerance (CAP theorem).

Latency vs Throughput

• Optimizing for low latence (quicker reponse time) may reduce the throughput (amount of work done in a period of time).

Security vs Usability

• More strict security measures may protect more the system, but also may reduce end user usability.

Memory storage vs Disk storage

• Memory storage (like caches) will offer quicker access to data, but it is more limited and more costly.

• Disk storage is usually more abundant and cheaper, but with slower access.

Stages

1. Finding out the Requirements

• To better understand the system we are developing.

• FRs and NFRs. (here)

2. Defining the Usecases

• Given the functionalities definined in the FRs, what can the user do with them.

  • How can the user interact with the application.

3. Do the Solution Design

• Choosing the tradeoffs.