Size of memory a variable reference (not size of type of variable)

Getting Help
1

I would like to know the size of memory a variable references (not the size of the type of variable, which is just 8 bytes or 16bytes).
I’m using unsafe.Sizeof(a) , but that gives me only the size of the type of variable a, not the memory referenced by the variable.
s := "abc"
s1:= “abcedffffffffffffffff”

unsafe.SizeOf returns 16 bytes on both string however s1 holds more content. Knowing the size of memory referenced by s or s1 will help me in many cases, and in case where I need to load millions of strings into memory for quick access.

Thanks.

2

That isn’t exposed and is implementation specific - small allocations will typically be rounded up, and so on. The closest you’ll get without making assumptions on the implementation is probably sizeof(thestring) plus len(thestring).

3

Thanks for the reply. With the len of string, how do we know the size of it? Are we assuming the size of each character in the string?

4

len on a string returns the length in bytes.

5

I dont think it is accurate to assume each character is a byte, although it is good assumption.

6

len("string") returns the length of a string in bytes, as @calmh said, not number of runes (or characters). For example, try running this playground: https://play.golang.org/p/xbC-S2Z7rR. What you’ll see is that the output is the length in bytes of a string and that they differ, even though the two strings have only one rune.

So, it’s fine to use len("string") to measure the size in bytes of a string’s content.

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7

The size of a pointer to a variable is one machine word, uintptr, or more directly 4 bytes in 32 bit platforms, and 8 bytes on 64 bit platforms.

9

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