What is the minimum contribution expected from an M.Sc. thesis? I am writing a thesis for my M.Sc. dissertation, and I am struggling to identify how big the contribution of my paper has to be.

I've heard professors in our campus saying "you don't have to save the world, just add a little bit of something to an already existing work." But that is vague and seems too little for an M.Sc. program. Do you have any advice on what could be considered a sufficient contribution? 

Ps. My field is distributed systems (cloud computing) and it would be nice if you could explain it in that context.
In my opinion and experience, it is relatively rare for an MSc thesis to yield truly original research resulting in a paper. The primary goal of a MSc thesis is to teach you important research skills: come up with a general idea of what to do, researching literature, coming up with a specific question that you want to address, performing research (computations, fieldwork, lab experiments), and finally writing it down in a thesis. If you successfully complete this cycle, I think your MSc thesis is a success. If the thesis, after some editing, is original enough to end up as a journal paper this is a big bonus.