No, it would probably be more performant to write a for loop, because broadcasting (or map) allocates an array for the result. If you don’t want to return anything, presumably you are doing something else, e.g. summing or something?
Loops are fast in Julia (if they are written properly). There’s nothing magical about broadcast operations except for the compact syntax — under the hood, they are implemented in Julia code with ordinary loops.
Let’s say I have a 1000×3 Matrix{Int64}.
Note that if you are working with a bunch of 3-component vectors, e.g. for 3d coordinates, you should consider using StaticArrays.
Note also that Julia arrays are stored column-major so accessing a 1000x3 array by rows will be less efficient than accessing a 3x1000 array by columns. (Or a length-1000 array of 3-component staticarrays.)