1. A method comprising: identifying, by a storage server, a workload from a plurality of different workloads generated by one of a plurality of applications and a plurality of computing devices, for using a data storage system; allocating at least a portion of a buffer cache in the data storage system to the identified workload by logically partitioning the buffer cache, without physically partitioning the buffer cache; establishing a soft-limit on allowable usage for the identified workload, above which additional usage of the buffer cache by the identified workload is degraded; determining if the identified workload is exceeding its allocated portion of the buffer cache; determining that usage of the buffer cache by the identified workload does not negatively impact performance of another workload and continue to use the buffer cache by the identified workload in excess of the allocated portion; and if the identified workload is exceeding its allocated buffer cache, by an excess, and negatively impacts performance of the another workload, making at least a portion of the excess amount available for scavenging by lowering a queue priority assigned to the identified workload.