Consistency Rationing in the Cloud: Pay Only When It Matters

Overview

Cloud storage solutions promise high scalability and low cost. Existing solutions, however, differ in the degree of consistency they provide. Its experience using such systems indicates that there is a non-trivial trade-off between cost, consistency and availability. High consistency implies high cost per transaction and, in some situations, reduced availability. Low consistency is cheaper but it might result in higher operational cost because of, e.g., overselling of products in a Web shop.