A processor includes a plurality of cores, at least two of which may execute redundantly, a configuration register to store a first synchronization domain indicator to indicate that a first core and a second core are associated with a first synchronization domain, and a power controller having a synchronization circuit to cause a dynamic adjustment to a frequency of at least one of the first and second cores to cause these cores to operate at a common frequency, based at least in part on the first synchronization domain indicator.