Patent ID: 8706688
Filing Date: 2014-04-22
Classification: G06F

Abstract:
1. A computer-implemented data storage system comprising: mapping logic executed by a processor configured to execute instructions stored in memory, the mapping logic configured to map responsibility for storing a plurality of data sets to a plurality of data centers and to a plurality of hosts within the plurality of data centers, the plurality of data centers corresponding to a ring topology; data set replication logic executed by a processor configured to execute instructions stored in memory the data set replication logic configured to write a first plurality of copies of a data set at a first subset of the plurality of hosts within a first subset of the plurality of data centers, the first subset of the plurality of data centers corresponding to a first ordered sequence of data centers around the ring topology from a starting data center on the ring topology, the first ordered sequence identified as a function of a multi-part key corresponding to the data set; data set retrieval logic executed by a processor configured to execute instructions stored in memory the data set retrieval logic configured to read a second plurality of copies of the data set at a second subset of the plurality of hosts within a second subset of the plurality of data centers; and data set comparison logic executed by a processor configured to execute instructions stored in memory, the data set comparison logic configured to evaluate causal relationships between elements of the second plurality of copies of the data set to provide a single copy of the data set, the evaluation of causal relationships including at least an evaluation of causal relationships between elements in the second plurality of copies of the data set that are not causal ancestors of other elements in the second plurality of copies of the data set.