In the context of problems associated with self-healing in autonomic computer systems, and particularly, the problem of fast and efficient real-time diagnosis in large-scale distributed systems, a “divide-and-conquer” approach to diagnostic tasks is disclosed. Preferably, parallel (i.e., multi-thread) and distributed (i.e., multi-machine) architectures are used, whereby the diagnostic task is preferably divided into subtasks and distributed to multiple diagnostic engines that collaborate with each other in order to reach a final diagnosis. Each diagnostic engine is preferably responsible for some subset of system components (its “region”) and performs the diagnosis using all available observation about these components. When the regions do not intersect, the diagnostic task is trivially parallelized.