Does accessing a single struct member pull the entire struct into the Cache?

Question

I\'ve been reading Ulrich Drepper\'s, \"What every programmer should know about memory\" and in section 3.3.2 Measurements of Cache Effects ( halfway down the page ) it gives me

Answer 1

The hardware doesn't know the layout of the struct, but just loads a number of bytes around the accessed member into cache. And yes, the slowdown from larger structs is because they will then be spread across more cache lines.