System requirements
Functional:
List functional requirements for the system (Ask the chat bot for hints if stuck.)...
1)Follow Each Other
2)Create Tweets
3)Access News Feed
Non-Functional:
List non-functional requirements for the system...
1)Availability
2)Scalability
Capacity estimation
Estimate the scale of the system you are going to design...
Total DAU - 500 Million
Each User Tweets twice a day.
Total Tweets - 500 Million * 2 = 1 billion
Total Views Of tweets in a day = 500Million * 100 = 50 Billion Tweets
Peak Traffic = 500 Million * 20% = 100 Million
LOAD ESTIMATION:
Each Tweet Size = 512 bytes
Total SIze of tweets in a day = 1 billion * 0.5 kb = 512 GB per day
Over a year = 512 gb * 365 days = 186 TB
2 years = 186 * 2 = 512 TB
API design
Define what APIs are expected from the system...
API's can be made for creating a tweet , follow/unfollow a user ,searching a Tweet , creating users , Editing user profile , Liking a twee, commenting , retweeting
Database design
Defining the system data model early on will clarify how data will flow among different components of the system. Also you could draw an ER diagram using the diagramming tool to enhance your design...
High-level design
You should identify enough components that are needed to solve the actual problem from end to end. Also remember to draw a block diagram using the diagramming tool to augment your design. If you are unfamiliar with the tool, you can simply describe your design to the chat bot and ask it to generate a starter diagram for you to modify...
Request flows
Explain how the request flows from end to end in your high level design. Also you could draw a sequence diagram using the diagramming tool to enhance your explanation...
Detailed component design
Dig deeper into 2-3 components and explain in detail how they work. For example, how well does each component scale? Any relevant algorithm or data structure you like to use for a component? Also you could draw a diagram using the diagramming tool to enhance your design...
Trade offs/Tech choices
Explain any trade offs you have made and why you made certain tech choices...
Failure scenarios/bottlenecks
Try to discuss as many failure scenarios/bottlenecks as possible.
Future improvements
What are some future improvements you would make? How would you mitigate the failure scenario(s) you described above?