1. A computer-implemented method for configuring a request-centric system, the method being executed using one or more processors and comprising: monitoring operation of the request-centric system to determine a workload of the request-centric system, wherein the workload comprises a plurality of requests, each of the plurality of requests being partitioned into slices of equal size and the request-centric system comprising at least one of a file storage system and a data storage system; determining a mapping function based on a utility function, the workload and a configuration, the mapping function mapping the workload and the configuration into the utility function, the configuration applying a slice-allocation policy to manage access of the slices to resources of the request-centric system and the utility function defining a utility of the request-centric system with respect to a plurality of predefined goals and comprises a sum of a plurality of penalties associated with agreed service levels not achieved by the request-centric system, each of the plurality of penalties being defined based on a service level type and an operation type; determining an optimal configuration based on the mapping function, the optimal configuration allocating the resources of the request-centric system to minimize the sum of the plurality of penalties by achieving a first of the plurality of predefined goals corresponding to a first service level type and violating a second of the plurality of predefined goals corresponding to a second service level type that is inferior to the first service level type; and applying the optimal configuration to the request-centric system to speed up processing of a portion of the slices that correspond to the first service level type.