System design

Question 1

what are some questions to keep in mind regarding th e system you are building?

Answer 1

How can we tell that the system is working?
Is there a bottleneck, single point of failure in the design?
How do all the components works together? (again single point of failure)

How can we scale and serve clients globally?

Question 2

What are some numerical component to keep in mind?

Answer 2

Latency (databases EC2 machines)
triughtput
storage

Question 3

System design template for interviews

Answer 3

1. Requirements
functional : what is needed (a user should see tweet etc)
non functional (but still required): 
High availability
Consistency
Latency
Reliability

2) Storage Estimation

What time of data, how much how to ensure requirements. Is it more writing or reading? (if reading cache it)

3) Database
SQL or NON SQL?
What type of replicas?

4) error handling failures *Throttling(

Start from

Basic design:
Client
Application server
Database

Then add