Patent ID: 8005793
Filing Date: 2011-08-23
Classification: G06F

Abstract:
1. A clustered storage system environment, comprising: a first node operatively connected to a first storage device and configured to store on the first storage device a volume comprising persistent point in time data to be migrated to a second node; a processor operatively connected to the first node and configured to execute a storage operating system, the storage operating system configured to create a plurality of persistent point in time data maps associated with the volume, each persistent point in time data map of the plurality of persistent point in time data maps configured to identify blocks in use and not in use for the volume; the storage operating system further configured to create a collective persistent point in time data map comprising a logical organization of the plurality of persistent point in time data maps; the first node further configured to transmit the collective persistent point in time data map and the volume to the second node without transmitting the plurality of persistent point in time data maps; the second node configured to store the volume and the collective persistent point in time data map on a second storage device operatively connected to the second node; the second node further configured to receive a data request for a block of the volume on the second storage device that is marked as in use by the collective persistent point in time data map; and the second node further configured to, in response to receiving the data request for the data block marked as in use, prevent allocation of the block.