Recent decades have witnessed an explosive growth in the amounts of digital data in various fields of arts, science and engineering. Such data is generally of interest to a large number of people spread over wide geographical areas. Over the years, several Distributed File Systems (DFS) have, to varying degrees, addressed this requirement of sharing large amounts of data, stored in the form of files, among several users and applications. Scalability and performance are two important measures that determine the suitability of a file system for the applications executing over them. We perform a detailed comparative analysis of popular distributed file systems in terms of these measures in our survey.