Patent ID: 8918390
Filing Date: 2014-12-23
Classification: G06F,H03M

Abstract:
1. A computer-implemented method for improving efficiency in a delta compression process in a data storage system, the method comprising: selecting a data chunk to delta compress; generating a sketch for the selected data chunk; searching for a set of candidate data chunks using the sketch; ranking the set of candidate data chunks by degree of sketch matching; tie-breaking the set of candidate data chunks, where the set of candidate data chunks has an equal degree of sketch matching, using location status data for each candidate data chunk, wherein the location status data indicates the location and status of the candidate data chunk and the location status data is at least one of a compressed in a cache status, a decompressed in a cache status, or a compressed in a data storage status, wherein tie-breaking the set of candidate data chunks prefers a decompressed in a cache status over a compressed in a cache status; delta compressing the selected data chunk with a selected candidate data chunk; and storing the delta compressed selected data chunk in the data storage system.