1. A computer implemented method for operating a first storage system having a first number of data storage drives for enabling access to a first set of removable media, the method comprising: providing a second storage system having a number K of data storage drives for enabling access to a second set of removable media, wherein K is greater than 1 and at least equal to the first number of data storage drives; providing a set of parameters describing operational characteristics of the second storage system; determining an analytical model using the set of parameters, the analytical model describing the variation of average waiting time as a function of system load over a predefined range covering multiple system load regime domains, wherein determining an analytical model comprises: splitting the predefined range into multiple subranges; determining an analytical model for each sub-range of the sub-ranges; and combining the determined analytical models of the sub-ranges into the analytical model of the predefined range; determining values of the set of parameters using the analytical model and data of the second storage system; and using the analytical model and the values of the set of parameters for reconfiguring the first storage system, wherein reconfiguring the first storage system includes activating and/or deactivating data storage drives of the first storage system.