Clock Snooping and its Application in on-the-fly Data Race Detection

In this paper, we describe clock snooping, a novel logical clock update technique that improves the performance of classical logical clocks (scalar clocks, vector clocks, as well as matrix clocks). The basic idea of clock snooping is that logical clocks will not only get updated with information piggybacked on communication messages, but that processes can explicitly request the current value of the clock of another process, and use that information to resynchronize its own clock. The usefulness of this concept is shown in our on-the-fly race detection software.