We are implementing a 'middlewear' layer to an underneath storage and
need to estimate costs for various system configurations.
Specifically, I want to estimate the resources (memory, disk) for our
data model.

Is there a tool that  given certain storage configuration parameters,
column family fields number and sizes and other details, and then
workload-dependant  parameters such as read/write average rates etc. can predict the
resource consumption (i.e, memory, disk)  in an offline mode?