Spectral analysis of timestamp data on unsynchronized computer systems

The MSU ERC UltraScope system consists of a distributed computing system, custom PCI cards, and GPS receivers. The UltraScope system allows precision timestamping of events in a distributed application on a system where the CPU and PCI clocks are synchronous. This paper investigates methods by which the UltraScope system can be expanded to asynchronous systems. The count offset and clock properties for an asynchronous system are computed. The spectrum of these characteristics are analyzed to try to improve the accuracy of the UltraScope system on this class of computing systems.