I was reading a book and came across this topic about passing parameters.
The book says passing a slice of an array to a function takes 24 bytes. And it states that it is better to pass the slice, because the underlying array will not be copied. But doesn't passing a pointer only take 8 bytes?
Book: Go in action
Is the overhead so little that passing slices is the way to go? Versus passing the pointers
分享 Copying anything less than a cache line (usually 128 bytes on most common CPUs) basically takes the same amount of time, so there's no real difference between 8 bytes and 24. More time is usually spent dereferencing the pointer than copying anything this small.
Since the default method of manipulating arrays via pointers is within a slice, it's more idiomatic to use a slice rather than a pointer to an array. The quote from the book however is referring to passing an array value, not via a pointer, which will copy the entire array.
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