Methods and systems for efficient file replication are provided. In some embodiments, one or more coarse signatures for blocks in a base file are compared with those coarse signatures for blocks of a revised file, until a match is found. A fine signature is then generated for the matching block of the revised file and compared to a fine signature of the base file. Thus, fine signatures are not computed unless a coarse signature match has been found, thereby minimizing unneeded time-consuming fine signature calculations. Methods are also provided for determining whether to initiate a delta file generation algorithm, or whether to utilize a more efficient replication method, based upon system and/or file parameters. In accordance with additional embodiments, the lengths of valid data on physical blocks are obtained from physical block mappings for the files, and these lengths and mappings are utilized for delta file generation, to minimize unnecessary signature computations.