A hard real-time system is a system that requires a guaranteed response to specific events within a defined time period

Foreword: This study compares the real-time capabilities of various Linux kernels. It was part of a project to upgrade the control software in water-wave generators at research institutions around the world. The results of the study were used by Akamina for the selection of a new RTOS for the control system upgrade of Canada's largest hydraulics and coastal engineering laboratory, the National Research Council Canadian Hydraulics Centre in Ottawa.