Patent ID: 7822758

Claim:
A method of operating a storage server, the method comprising: executing, by the storage server, a process of restoring a data set in an active file system of the storage server from a persistent point-in-time image (PPI) by updating a plurality of pointers in the active file system to reference data blocks of the PPI, wherein the updating comprises modifying at least one of the plurality of pointers to associate a block of the PPI with the data set; and during said process of restoring the data set from the PPI, servicing a request for a data block, wherein the request is directed at the data set by a client of the storage server by, in response to determining that a pointer corresponding to the requested data block points to a block in the data set that does not contain valid data, sending the requested data block to the client before said process of restoring is completed, wherein the requested data block is retrieved from the PPI.