240 Go Interview Questions with Answers – Master Them in 3 Passes to Land the Job

Go Fundamentals

What advantages does Go have compared to other languages?

What data types does Go use?

What is a package in Go?

How does type conversion work in Go (e.g., converting an integer to a float)?

What is a goroutine and how can you stop it?

How to check a variable's type at runtime?

What relationships can exist between two interfaces?

What are the characteristics and purpose of Go's synchronization locks?

What are the features of Go channels and what should be noted?

What are the characteristics of buffered channels?

What can the CAP function be applied to?

What is GO CONVEY and its typical use?

What is the difference between new and make in Go?

What is the purpose of make?

How do printf, sprintf, and fprintf differ?

What is the difference between arrays and slices?

How are value passing and reference passing used in Go? Provide examples.

How does slice expansion work internally?

What is the execution order of defer statements and their characteristics?

What is the underlying implementation of Go slices?

What are the expansion mechanisms and precautions for Go slices?

How does parameter passing work for reference types?

How does the Go map work internally and how does it expand?

How does map lookup work?

How does channel work and its ring‑buffer implementation?

Go Concurrency

What are the different states of a mutex?

What are the normal and starvation modes of a mutex?

Under what conditions can a mutex spin?

How is an RWMutex implemented?

What are the precautions when using an RWMutex?

What is a condition variable (COND)?

What is the difference between broadcast and signal?

How is wait used in a condition variable?

How to use a WaitGroup and its implementation principle?

What is sync.Once?

What constitutes an atomic operation?

What is the difference between atomic operations and locks?

What is CAS?

What is the purpose of sync.Pool?

Go Runtime

Definition of a goroutine.

What does GMP stand for?

What was the scheduling model before Go 1.0?

How does the GMP scheduling process work?

What is the work‑stealing mechanism in GMP?

What is the hand‑off mechanism in GMP?

How does cooperative preemptive scheduling work?

What is signal‑based preemptive scheduling?

What blocking situations exist during GMP scheduling?

What is the role of SYSMON?

What is the three‑color marking principle?

What are insertion write barriers?

What are deletion write barriers?

What are write barriers in general?

What are mixed write barriers?

When is GC triggered?

What is the GC process in Go?

How to tune GC?

Microservices

What is your understanding of microservices?

What are the advantages of microservice architecture?

What characteristics define microservices?

What are the best practices for designing microservices?

How does a microservice architecture operate?

What are the pros and cons of microservice architecture?

Differences among monolith, SOA, and microservices.

Challenges faced when using microservices.

Key differences between SOA and microservices.

What is domain‑driven design (DDD) and why is it needed?

What is an ubiquitous language?

What is cohesion and coupling?

What is REST/RESTful and its purpose?

Types of microservice testing.

Container Technology

Why is DevOps needed?

What is Docker?

What advantages does DevOps bring?

What is the purpose of CI services?

How to create environment‑agnostic containers with Docker?

Difference between COPY and ADD in a Dockerfile.

What is a Docker image?

What is a Docker container?

What is Docker Hub?

Possible runtime states of a Docker container.

How to determine a container's running status?

Commonly used Dockerfile instructions.

Which application types suit Docker best?

Basic Docker workflow.

Difference between Docker image and Docker layer.

What is virtualization technology?

What is a hypervisor?

What is Docker Swarm?

How to monitor Docker in production?

What is a container image and how to delete it?

What is paravirtualization?

Differences between Docker and virtual machines.

Purpose of the ONBUILD instruction in Dockerfile.

Running stateful Docker applications and best practices.

Running Docker on Windows and non‑Linux platforms.

Underlying principles of containerization.

Pros and cons of containerization vs. virtualization.

How Docker adapts to multiple runtime environments.

Why Docker Compose starts containers without waiting for dependencies.

Redis

What is Redis?

What data types does Redis provide?

Benefits of using Redis.

Advantages of Redis over Memcached.

Differences between Memcached and Redis.

Is Redis single‑process and single‑threaded?

Maximum capacity of a character‑type value?

Persistence mechanisms of Redis and their trade‑offs.

Common performance problems and solutions.

How are expired keys handled?

What are Redis eviction policies?

Why does Redis keep all data in memory?

How does Redis replication work?

Differences between Jedis and Redisson.

How to set passwords and authenticate?

What is the concept of hash slots?

How does Redis cluster master‑slave replication work?

Can write operations be lost in a Redis cluster? Why?

How many nodes can a Redis cluster have?

How to test Redis connectivity?

Understanding Redis transactions and related commands.

How to set expiration vs. permanent keys?

How to optimize Redis memory usage?

How does the Redis reclamation process work?

Ways to reduce Redis memory consumption.

What happens when Redis memory is exhausted?

Maximum number of keys a Redis instance can store.

Strategies for keeping hot data in Redis.

How to efficiently locate millions of keys with a common prefix.

Considerations when setting expiration for a large number of keys.

Using Redis as an asynchronous queue.

Using Redis for distributed locks.

MySQL

What are the three normal forms?

Which tables store MySQL permission information?

What are the formats of MySQL binlog and their differences?

Differences between MyISAM and InnoDB storage engines.

Differences between MyISAM and InnoDB indexes.

What is an index?

Advantages and disadvantages of indexes.

Types of storage engines.

Types of locks in MySQL.

Four transaction isolation levels supported by InnoDB and their distinctions.

Difference between CHAR and VARCHAR.

Difference between primary key and candidate key.

How to convert between UNIX timestamp and MySQL timestamp.

Where does MyISAM store its data and what format?

Best field type for storing currency.

Precautions when creating indexes.

Can indexes always improve query performance?

How to delete data at the million‑row scale.

What is the leftmost‑prefix principle?

What is a clustered index and when to use it?

MySQL connector overview.

MySQL query cache.

MySQL parser, optimizer, executor.

What are temporary tables and when to drop them?

Experience with MySQL optimization.

What are external and internal links?

Things to note when using UNION and UNION ALL.

Characteristics of MyISAM and InnoDB storage engines.

The article provides the full list of questions (240 in total) and their answers, allowing readers to study each topic repeatedly and build confidence for Go development interviews.