Patent ID: 7290101

Claim:
A method comprising: creating a point-in-time (PIT) copy of a data volume, wherein the data volume comprises a plurality of data blocks including a first data block; creating a map in memory, wherein the map comprises a plurality of entries, wherein each entry of the map indicates whether memories allocated to store data of respective data blocks of the data volume and the PIT copy, contain identical data; generating an I/O transaction to read data from or write data to memory allocated to store data of the first data block of the data volume; if an entry in the map indicates that identical data is stored in memories allocated to the first data block of the data volume and a first block of the PIT copy, respectively: reading data from memory allocated to store data of the first block of the PIT copy; and allowing I/O transactions to complete using the data read from memory allocated to store data of the first block of the PIT copy, without first accessing a transaction log associated with the data volume.