Patent ID: 7702873

Claim:
A method comprising: receiving, at a storage server, an indication to set a space reservation for a volume associated with a logical aggregation of physical storage, wherein the logical aggregation of physical storage provides an abstraction layer between the volume and a physical storage; reclaiming space from one or more space-reclaimable volumes that organize space within the logical aggregation of physical storage if the logical aggregation of physical storage does not have enough free space to reserve a specified amount of storage space for the volume to provide a requested storage capacity for the volume according to the space reservation, wherein reclaiming space includes determining an amount of space-reclaimable available from the one or more space-reclaimable volumes if the volume accepts a delayed space reservation, and delaying setting of the space reservation for the volume until a sufficient amount of space is reclaimed from the one or more space-reclaimable volumes, wherein the delaying includes detecting a plurality of allocated, unreserved blocks of the one or more space-reclaimable volumes, performing at least one of truncating and compressing data in the detected blocks to create a free space reserve, and reserving the specified amount of the logical aggregation of physical storage for the volume as a delayed space reservation according to the free space reserve; and granting the delayed space reservation for the volume until the sufficient amount of space is reclaimed from the one or more space-reclaimable volumes associated with the logical aggregation of physical storage to provide the requested storage capacity for the volume, wherein the logical aggregation of physical storage provides a common pool of physical storage shared between at least one space-reclaimable volume and at least one non-space-reclaimable volume and the sufficient amount of storage space to provide a requested storage capacity for the volume is reclaimed from the space-reclaimable volume.