TMO-Linux: a Linux-based real-time operating system supporting execution of TMOs

The TMO (time-triggered message-triggered object) model is a well-known real-time object model for distributed and timeliness-guaranteed computing. We developed two TMO execution engines, named WTMOS and LTMOS, the former is for Windows platforms and the latter is for Linux platforms. Those are middleware engines supporting deadline driven real-time execution of TMO methods and distributed IPC. The engines have several advantages such as heterogeneous computing support, flexibility, and high portability. However, the deadline-driven schedulers of the middlewares lose temporal accuracy in some cases because the scheduling is performed by controlling priorities of real-time threads. To increase temporal accuracy and reduce overhead by middlewares, we developed a new Linux-based operating system named "TMO-Linux" that supports distributed real-time execution of TMO instances as embedded services of an operating system. In this paper, we present the functions and structure of TMO-Linux. Our preliminary experimental results show that TMO-Linux has better timing accuracy and performance than the middleware engines.