Why microservices exist - Challenge Your Understanding

Challenge - 5 Problems

🧠 Conceptual

intermediate

Why do microservices help with scaling?

Imagine a large online store that suddenly gets many visitors. Why would breaking the store's system into microservices help it handle more visitors better?

A Because microservices combine all functions into one big program that runs faster.

B Because each microservice can be scaled independently to handle specific tasks without scaling the whole system.

C Because microservices reduce the number of servers needed by merging services.

D Because microservices store all data in one place to speed up access.

💡 Hint

Think about how different parts of a system might need different amounts of resources.

Microservices allow parts of a system to be scaled separately. For example, the payment service can be scaled up without scaling the product catalog service, making resource use efficient.

❓ Architecture

intermediate

Which architecture best shows why microservices exist?

Look at these system designs. Which one best explains why microservices are used?

A Multiple small services each handling a specific function, communicating over a network.

B A single large application where all functions are tightly connected in one codebase.

C A monolithic database accessed by many small scripts running on one server.

D A desktop application that runs all services locally without network communication.

💡 Hint

Think about separation of concerns and independent deployment.

Microservices architecture splits a system into small, independent services that communicate over a network, allowing easier updates and scaling.

❓ tradeoff

advanced

What is a main tradeoff when choosing microservices?

Microservices offer many benefits but also have downsides. Which of these is a common tradeoff when using microservices?

A Increased complexity in managing many services and their communication.

B Reduced ability to update parts of the system independently.

C Lower fault tolerance because all services run on one server.

D Simpler deployment since everything is in one package.

💡 Hint

Think about what happens when you have many small parts instead of one big part.

Microservices increase complexity because you must manage many services, their communication, and data consistency, even though they allow independent updates.

❓ scaling

advanced

How do microservices improve fault isolation?

When one part of a system fails, microservices can help limit the problem. How do microservices improve fault isolation?

A By running all functions in one process so errors affect everything equally.

B By combining all logs into one file to detect errors faster.

C By sharing a single database that stops working if one service fails.

D By isolating services so failure in one does not directly crash others.

💡 Hint

Think about how separating parts can prevent one failure from spreading.

Microservices run independently, so if one service crashes, others can continue working, improving system reliability.

❓ estimation

expert

Estimate the impact of microservices on deployment frequency

A company moves from a monolithic system to microservices. How does this change affect how often they can deploy updates?

A Deployment frequency stays the same because the system size does not change.

B Deployment frequency decreases because coordinating many services is harder.

C Deployment frequency increases because small services can be updated independently.

D Deployment frequency stops because microservices require full system redeployment.

💡 Hint

Think about how independent parts can be updated without waiting for others.

Microservices allow teams to deploy updates to individual services without redeploying the entire system, increasing deployment frequency.

Practice

1. Why do organizations choose microservices over a single large application?

easy

A. To write all code in one programming language

B. To make the system run only on one server

C. To avoid using any databases

D. To break a big system into smaller, manageable parts

Solution

1. Step 1: Understand the problem with large applications

   Large applications are hard to manage, update, and scale because everything is tightly connected.

2. Step 2: Identify microservices benefit

   Microservices split the big system into smaller parts that can be managed and updated independently.

3. Final Answer:

   To break a big system into smaller, manageable parts -> Option D

4. Quick Check:

   Microservices = smaller parts [OK]

Hint: Microservices split big apps into small parts [OK]

Common Mistakes:

• Thinking microservices run only on one server
• Believing microservices avoid databases
• Assuming microservices require one language

2. Which of the following is a key feature of microservices architecture?

easy

A. All services share the same database schema

B. Each service can be developed and deployed independently

C. Services must be written in the same programming language

D. Microservices require a monolithic deployment

Solution

1. Step 1: Review microservices independence

   Microservices allow teams to develop and deploy each service without affecting others.

2. Step 2: Check other options

   Sharing the same database or language is not required; monolithic deployment contradicts microservices.

3. Final Answer:

   Each service can be developed and deployed independently -> Option B

4. Quick Check:

   Independent deployment = microservices [OK]

Hint: Microservices = independent deploys [OK]

Common Mistakes:

• Assuming all services share one database
• Believing all code must be in one language
• Thinking microservices deploy as one unit

3. Consider a system split into microservices: User Service, Order Service, and Payment Service. If the Order Service crashes, what is the likely impact on the User Service?

medium

A. User Service continues working independently

B. User Service will lose all user data

C. User Service will also crash immediately

D. User Service will restart automatically

Solution

1. Step 1: Understand microservices isolation

   Each microservice runs independently, so failure in one does not crash others.

2. Step 2: Analyze impact on User Service

   User Service can keep working even if Order Service crashes, though some features may be limited.

3. Final Answer:

   User Service continues working independently -> Option A

4. Quick Check:

   Microservices isolation = independent operation [OK]

Hint: Microservices fail independently, not together [OK]

Common Mistakes:

• Assuming one service crash crashes all
• Thinking user data is lost when order fails
• Believing services auto-restart always

4. A team built a microservices system but notices that deploying one service requires stopping the entire system. What is the likely mistake?

medium

A. Services are tightly coupled and not independent

B. They are using too many programming languages

C. The database is too large

D. They did not write enough tests

Solution

1. Step 1: Identify deployment problem

   If deploying one service stops the whole system, services are not independent as microservices require.

2. Step 2: Rule out other options

   Programming languages, database size, or tests do not cause deployment to stop all services.

3. Final Answer:

   Services are tightly coupled and not independent -> Option A

4. Quick Check:

   Independent services = independent deploys [OK]

Hint: Independent deploy means no system-wide stop [OK]

Common Mistakes:

• Blaming programming languages for deployment issues
• Thinking database size causes deployment stop
• Assuming tests affect deployment independence

5. A company wants to scale their online store quickly during sales. How does microservices architecture help achieve this?

hard

A. By forcing all services to scale together as one unit

B. By allowing only the payment service to scale independently

C. By enabling each service to scale based on its own demand

D. By removing the need for any scaling

Solution

1. Step 1: Understand scaling in microservices

   Microservices let each part of the system scale separately depending on its load.

2. Step 2: Apply to online store scenario

   During sales, services like Order or Payment can scale more without scaling unrelated services.

3. Final Answer:

   By enabling each service to scale based on its own demand -> Option C

4. Quick Check:

   Microservices scale independently = efficient scaling [OK]

Hint: Scale each service separately for efficiency [OK]

Common Mistakes:

• Thinking only one service scales
• Believing all services must scale together
• Assuming microservices remove scaling needs