First microservice architecture diagram in Microservices - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Architecture

intermediate

Identify the main components in a simple microservice architecture

Look at a basic microservice architecture diagram with these components: API Gateway, User Service, Order Service, Database, and Message Queue.

Which component handles client requests first?

A User Service

B API Gateway

C Database

D Message Queue

💡 Hint

Think about which part acts as the entry point for all client requests.

The API Gateway is the first component that receives client requests and routes them to the appropriate microservice.

❓ scaling

intermediate

Scaling microservices for high traffic

You have a microservice that handles user profiles. Traffic is increasing rapidly. Which approach best supports scaling this microservice?

A Combine User Service and Order Service into one service

B Add more CPU cores to the database server

C Use a single instance with more memory

D Deploy multiple instances of the User Service behind a load balancer

💡 Hint

Think about horizontal scaling and distributing load.

Deploying multiple instances behind a load balancer allows the service to handle more requests by distributing traffic.

❓ tradeoff

advanced

Choosing between synchronous and asynchronous communication

In a microservice architecture, what is a key tradeoff when choosing asynchronous messaging over synchronous HTTP calls?

A Asynchronous messaging improves system resilience but increases complexity in data consistency

B Asynchronous messaging reduces latency but causes tight coupling between services

C Synchronous HTTP calls improve fault tolerance but reduce throughput

D Synchronous HTTP calls eliminate the need for message brokers

💡 Hint

Consider how asynchronous communication affects system design and data handling.

Asynchronous messaging allows services to continue working if others are slow or down, improving resilience, but it makes keeping data consistent harder.

🧠 Conceptual

advanced

Understanding service discovery in microservices

What is the main purpose of a service discovery component in a microservice architecture?

A To store user data securely

B To balance load between database replicas

C To allow services to find and communicate with each other dynamically

D To cache responses for faster access

💡 Hint

Think about how services know where other services are located.

Service discovery helps services locate each other’s network addresses dynamically, enabling communication without hardcoding locations.

❓ estimation

expert

Estimating capacity for a microservice handling 10,000 requests per second

You design a microservice expected to handle 10,000 requests per second. Each request takes 50ms CPU time on average. How many instances are needed to handle the load without queuing?

A At least 500 instances

B At least 200 instances

C At least 100 instances

D At least 50 instances

💡 Hint

Calculate total CPU time per second and divide by CPU time per instance.

Each request takes 0.05 seconds CPU time. 10,000 requests per second means 500 CPU-seconds needed per second. One instance (assuming 1 CPU core) can handle 1 CPU-second per second. So, 500 instances are needed to handle the load without queuing.