Comparing the real-time performance of Windows NT to an NT real-time extension

Because of the dominance of Microsoft(R) Windows(R) in the PC market there is a strong interest in using Windows NT(R) as a platform for real-time process and control systems. This type of solution is very cost effective because applications and development tools are widely available. However, Windows NT was designed as a general purpose operating system and optimizes average not worst case performance. We investigate two methods to bring real-time process and control systems to NT based platforms. We first evaluate NT as-is, using a series of real-time benchmarks, and show that NT use in real-time systems is limited to soft real-time systems where there is low system load. The second approach for developing NT based real-time systems is to add a real-time extension to NT. We evaluate one such product, INtime(R) from RadiSys and conclude that, even under a heavy system load hard real-time determinism is possible.