A technique is disclosed for distributed runtime diagnostics in hierarchical parallel environments. In one embodiment, a user is allowed to configure, during runtime, a processing element on which to perform diagnostics, an algorithm for the processing element to execute, a data set for the algorithm to execute against, a diagnostic function for the processing element to execute, a condition for executing the diagnostic function, and visualization parameters for memory local to the processing element. As a result, runtime diagnostics can be performed with sufficient degree of control and customization to aid debugging in a hierarchical parallel environment.