CLOS Operating System Family

CLOS is a technology and family of embedded operating systems supporting multicore architectures, with enhanced safety (DO-178C) and secure software development lifecycle (SSDL) requirements. CLOS provides spatial (memory) and temporal (response time guarantees) isolation of functional and system software. RTOS overhead is minimized through static memory configuration and nonperiodic timers with quantization. This article briefly describes the history of work on operating systems based on the microkernel approach, which began under the leadership of Academician V.P. Ivannikov in the 1970s and the development they have undergone to date. The main architectural solutions used in CLOS versions developed at the Institute of System Programming of the Russian Academy of Sciences for aerospace systems over the past ten years are described in more detail.