US Patent 8712978 Preferential selection of candidates for delta compression

A computer-implemented method and system for improving efficiency in a delta compression process in a data storage system selects a data chunk to delta compress and selects a set of candidate data chunks using a first selection mechanism. Throughput or resource utilization is monitored. A change is made to a second selection mechanism that increases similarity of the set of candidates with the selected data chunk to improve compression in response to determining high resource availability or high throughput level. A change is made to a third selection mechanism that increases throughput of the delta compression process in response to determining low resources availability or low throughput.