Chronos performs timing analysis of embedded software through static analysis. In particular, Chronos estimates Worst Case Execution Time (WCET), which is the upper bound on the execution time of a program over all possible data inputs on a specific hardware platform. WCET of a task is an essential input to the schedulability analysis of hard real-time systems. It is difficult to estimate the WCET through simulation for any non-trivial program due to the very large number of possible inputs. Thus static analysis techniques are employed to derive an upper bound on the WCET of a program.

One important yet difficult problem for static timing analysis is to model the timing effects of complex micro-architectural features present in modern processors, such as out-of-order execution, branch prediction, instruction and data caches. Chronos accurately models various architectural features (including out-of-order execution, branch prediction, instruction cache) and their interactions for WCET analysis.

Chronos is an open source software developed at National University of Singapore (NUS) specifically for the academic research community. It supports the widely popular SimpleScalar simulator infrastructure so that the user can easily extend and adapt the analyzer.

Chronos, in ancient Greek mythology, was the personification of time.