that link doesn't work for me. 

there's two aspects here and they are orthogonal to each other:

(A) - comparing jobs with each other and with available space on machines for the purpose of assigning a machine to run a job
(B) - actually enforcing the declared job requirement and not letting the job consume more than that

For the Cores resource, it doesn't really matter what we choose as long as we can express fractions of cores too. For (A) it really doesn't matter the semantics of these values and their units. It could be apples or matchsticks and it would work. We're just comparing them.

For (B) we need to map it into whatever low-level thingie will enforce the resource consumption on the machine, be it cpu shares or something else that comes out of cgroups. I also expect that this will be straightforward, a linear function f(x) = a x probably.