Efficient name space organization in a global name space cluster

Abstract

Described is a system for reclaiming unused storage space when distributing backup data to storage performance-based tiers within a clustered storage environment. The clustered storage environment may organize nodes into storage performance tiers, and each node within a tier may be tuned for a particular type of workload. Accordingly, the system implements a file system that provides the ability to reclaim unused storage space (e.g. perform garbage collection) for specific nodes or tiers independently despite implementing a global namespace. The global namespace may group (or co-locate) aspects of file information with the backup files. For example, file information may be stored on the same node that stores the associated backup files. Accordingly, the system may reclaim unused storage space for each node, or set of nodes forming a storage performance tier, independently and efficiently.