Docker on Amazon Web Services

Calculating the container capacity

One key consideration when calculating the capacity of your cluster is that you need to normalize your resource capacity calculations, such that the capacity of each resource can be expressed in a common and equivalent format, independent of the specific units of measurement for each individual resource. This is critical in making a collective decision that considers all resources, and a natural way to do this is to express resource capacity in terms of the number of additional ECS tasks that can be supported using the currently available unallocated resources. In addition, keeping with the theme of worst-case scenarios, you don't need to consider all of the different ECS tasks that you need to support