Patent ID: 7251660

Claim:
A method of determining an logical time value to real time value (LTV-to-RTV) mapping in a system, comprising the steps of: if a first event occurs, then writing a first logical time value to real time value (LTV-to-RTV) mapping to a first mapping data structure; if a second event occurs, then: determining whether a first set of conditions are satisfied, wherein determining whether the first set of conditions is satisfied comprises determining whether there are one or more logical time value to real time value LTV-to-RTV mappings in the first mapping data structure that are newer than all logical time value to real time value (LTV-to-RTV) mappings in a second mapping data structure; if the first set of conditions are satisfied, then: writing one or more logical time value to real time value (LTV-to-RTV) mappings to the second mapping data structure based on those logical time value to real time value (LTV-to-RTV) mappings in the first mapping data structure that are newer than all logical time value to real time value (LTV-to-RTV) mappings in the second mapping data structure; and determining, and storing in a computer-readable storage medium, a logical time value (LTV) for a particular real time value (RTV), based on the particular real time value (RTV) and information in a source of a set of sources, wherein the set of sources comprises the first mapping data structure and the second mapping data structure.