Golang中的sync.Mutex和* sync.Mutex哪个更好？

Question

In Golang, we can use:

type Data struct {
    lock  *sync.Mutex
}

or

type Data struct {
    lock  sync.Mutex
}

And, use like this:

func (d *Data) Update() {
   d.lock.Lock()
   defer d.lock.Unlock()
   // update
}

The difference I can think of is that *sync.Mutex needs instantiation to use only.

What is the difference between sync.Mutex and *sync.Mutex in Golang and which one is better?

Answer 1

• I think you can regard *sync.Mutex as a simple pointer. If you want to use it, you should declare and init it, but if you use sync.Mutex, it has been inited.
• BTW, in k8s source code, they always pass variable pointer to use, because passing struct will do a copy, but if you use pointer, all you need to pass is a pointer. ( I mean is you don't not need to have a copy spend).