Cooperative storage management

#This application is related to U.S. application. Ser. No. 13/286,106, filed Oct. 31, 2011, entitled “Virtual Full Backups,” the entire contents of which is hereby incorporated by reference as if fully set forth herein.

#The present invention relates generally to storage management and, more specifically, to coordinating shared backup storage space.

#Data storage devices are subject to data loss from a variety of causes, such as disk failure, unintentional deletion, malicious software attacks, or natural disaster. A common practice to guard against data loss is to create backup copies of important data and store them at a remote storage location. In the event of data loss or corruption, the backup copies are used to restore the lost or corrupted data to a previous state.

#The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:

#FIG. 1 is a block diagram of a system in which backup storage for multiple clients is managed by a storage system in accordance with an embodiment;

#FIG. 2A is a flowchart that illustrates a method for determining which backup data to delete in accordance with an embodiment;

#In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, that the present invention may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring the present invention.

#Techniques are described herein for cooperatively managing backup data for multiple client systems in a manner that allows for more efficient disk usage and better economy of scale. In particular, techniques are provided in which a storage server determines how to phase out backup data based, at least in part, on retention duration goals associated with the client systems. Consequently, the storage server may manage backup storage in such a way as to try and meet each client system's goals.

#According to embodiments described herein, a storage server stores backup data for a plurality of client systems, including a first client system and one or more other client systems. The storage server receives a request from the first client system to store new backup data. In response to the request from the first client system, the storage server determines which backup data to delete to make space for the new backup data based not only on the retention duration goals of the first client system that needs more storage, but also on the retention duration goals of one or more other client systems.