GO Goroutines and Concurrency 2

Question 1

What is a race condition in Go?

Accepted Answer

Two goroutines accessing shared memory without proper synchronization

Answer

A race condition occurs when two or more goroutines access shared memory concurrently and at least one access is a write, without synchronization.

Question 2

How do you detect race conditions when running Go tests?

Accepted Answer

go test -race

Answer

The `-race` flag enables Go's built-in race detector, which instruments the code to report data races at runtime.

Question 3

Which `sync` type allows multiple concurrent readers but only one writer at a time?

Accepted Answer

sync.RWMutex

Answer

`sync.RWMutex` provides `RLock`/`RUnlock` for multiple concurrent readers and `Lock`/`Unlock` for exclusive write access.

Question 4

What is the purpose of `sync.Once`?

Accepted Answer

Execute a function exactly one time across all goroutines

Answer

`sync.Once` guarantees that a function is executed exactly once, regardless of how many goroutines call `Do`, making it ideal for initialization.

Question 5

What does the Go scheduler use as its concurrency model?

Accepted Answer

M:N threading (many goroutines on fewer OS threads)

Answer

Go uses an M:N scheduler that multiplexes many goroutines (M) onto a smaller number of OS threads (N), managed by the Go runtime.

GO - Golang Online Test Practice Test