Patent ID: 7627614

Claim:
A method comprising the computer-implemented steps of: reading, from a read log that is updated when data units are read, a first version indicator that indicates a current version of a first instance of a data unit, wherein the first version indicator was written into the read log in response to the first instance of the data unit being read; reading a second version indicator that indicates the version of a second instance of the data unit; determining that the first version indicator does not indicate the same version of the data unit as the second version indicator; and in response to determining that the first version indicator does not indicate the same version as the second version indicator, then performing one or more specified actions relative to at least one of the first instance of the data unit and the second instance of the data unit, wherein the step of performing the one or more specified actions relative to at least one of the first instance of the data unit and the second instance of the data unit comprises flagging at least one of the first instance of the data unit and the second instance of the data unit as containing unreliable data, and wherein the steps of reading, determining, and performing are performed by a computing device.