在golang中实现缓存还是锁定？

package main

import (
    "fmt"
    "sync"
    "time"
)

var (
    cache = make(map[string]string)
    mutex sync.Mutex
)

func getFromCache(key string) (string, bool) {
    mutex.Lock()
    defer mutex.Unlock()

    value, ok := cache[key]
    return value, ok
}

func setToCache(key, value string) {
    mutex.Lock()
    defer mutex.Unlock()

    cache[key] = value
}

func main() {
    go func() {
        setToCache("key", "value")
    }()

    time.Sleep(time.Second)

    value, ok := getFromCache("key")
    if ok {
        fmt.Println("Value:", value)
    } else {
        fmt.Println("Key not found")
    }
}