Integration---supporting multiple application classes with heterogeneous requirements---is an emerging trend in networks, file systems, and operating systems. In this paper, we evaluate two architectural alternatives---partitioned and integrated---for designing next generation file systems. Whereas a partitioned server employs a separate component file system for each application class, an integrated file server shares its resources across all application classes. We evaluate the performance of these two architectures with respect to sharing of disk bandwidth. We show that although the problem of sharing disk bandwidth in integrated file systems is conceptually similar to that of sharing network link bandwidth in integrated services networks, the arguments that demonstrate the superiority of integrated services networks are not applicable to file systems. We experimentally evaluate the efficacy of sharing disk bandwidth and show that: (i) an integrated server outperforms the partitioned server in a large operating region and has slightly worse performance in the remaining region, (ii) the capacity of an integrated server is larger than that of the partitioned server, and (iii) an integrated server outperforms the partitioned server by up to a factor of 6 in the presence of bursty workloads.