1. Scalability & High Availability 개요

• Scalability means that an application / system can handle greater loads by adapting
• There are tow kinds of scalability:
  • Vertical Scalability
  • Horizontal Scalability(= elasticity)
• Scalability is linked but different to High Availability

2. Vertical Scalability

<aside>

📞 콜센터를 예시로 한다면 업무 처리 속도를 높이기 위해 주니어 상담원을 시니어 상담원으로 교체한다.

</aside>

• Vertical Scalability means increasing the size of the instance
• For example, your application runs on a t2.micro
• Scaling that application vertically means running it on a t2.large (t2.micro ⇒ t4.micro)
• Vertical scalability is very common for non distributed systems, such as a database.
• There’s usually a limit to how much you can vertically scale (hardware limit)

3. Horizontal Scalability

<aside>

📞 콜센터를 예시로 한다면 업무 처리 속도를 높이기 위해 상담원 숫자를 늘린다.

</aside>

• Horizontal Scalability means increasing the number of instances / systems for your application