Methods and systems for file replication utilizing differences between versions of files

摘要

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.

主权项

1. A method for determining whether to create a delta file reflecting differences between a base file and a revised version of the base file, the method comprising:
obtaining, by a computer system, one or more system parameters relating to resources of the computer system; determining, by the computer system, a threshold change amount between the base file and the revised version of the base file, wherein the threshold change amount is determined based on the obtained one or more system parameters and wherein the one or more system parameters comprise parameters indicating available network bandwidth, storage space, and CPU processing capacity; determining, by the computer system, whether differences between the base file and the revised version of the base file exceed the determined threshold change amount between the base file and the revised version of the base file; and in response to determining the threshold change amount is exceeded, avoiding, by the computer system, completion of the delta file and transmitting a copy of the revised version of the base file for replication purposes.