Tell about garbage collection in Go.

Go uses a concurrent, trigger-based garbage collector with a mark-and-sweep algorithm that runs in parallel with the program execution (concurrent GC). This minimizes pause times for garbage collection and maintains low latency.

Main features:

• Automatic memory management — developers do not need to explicitly free memory.
• Parallel operation — the garbage collector runs concurrently with main goroutines.
• Incremental and trigger-based — collection is triggered when a certain memory usage threshold is reached.

Example of simple code where the garbage collector frees unused memory:

package main

import (
    "fmt"
    "runtime"
)

func main() {
    var m runtime.MemStats

    // Create a large slice
    data := make([]byte, 10<<20) // 10 MB
    fmt.Println("Allocated 10MB")

    // Release the reference
    data = nil

    // Manually trigger garbage collection
    runtime.GC()

    runtime.ReadMemStats(&m)
    fmt.Printf("HeapAlloc = %v MiB\n", m.HeapAlloc/1024/1024)
}

In this example, after nullifying the reference and calling runtime.GC(), the memory occupied by the slice will be freed.