Patent ID: 9009106
Filing Date: 2015-04-14
Classification: G06F

Abstract:
1. A computer-implemented method for implementing a writable snapshot that is performed using a processor, comprising: identifying a parent snapshot; creating a child snapshot, in which the child snapshot is to be accessed in place of the parent snapshot without immediately copying all of the contents of the parent snapshot to the child snapshot; and creating a writable child snapshot, in which modifications can be made to the content of the writable snapshot and in which the writable snapshot can be accessed without immediately copying all of the contents of the parent snapshot to the writable snapshot, in which future data requests for the parent snapshot are directed to the child snapshot, in which a data request is made for a portion of the child snapshot or the writable snapshot which has not been copied from the parent snapshot and in which the data request is redirected to the parent snapshot, in which a data item is copied from the parent snapshot to the child snapshot or the writable snapshot upon a need to access the data item in the child snapshot or the writable snapshot in which a data item is copied from the parent snapshot to the child snapshot or the writable snapshot upon a need to access the data item in the child snapshot or the writable snapshot, in which a first portion of the data item exists in the writable snapshot and a second portion of the data item is referenced to the parent snapshot, in which metadata is used to track referencing between the child snapshot and the parent snapshot.