CPU schedulers are usually designed to allocate resources fairly among processes. In this paper, we describe Share, a scheduler that allocates resources so that users get their fair machine share over a long period.
We also describe an hierarchical form of Share that supports sharing, not only between individual users, but also between groups of users. In particular, it supports the sharing of a machine between organisational groups who are independently funded and have contributed a proportion of the machine cost. The hierarchical Share ensures that each group is allocated its defined machine share in the long term.