An Operating System for Safety-Critical Applications on Manycore Processors

Abstract

Processor technology is advancing from bus-based multicores to network-on-chip-based manycores, posing new challenges for operating system design. In this paper, we discuss why future safety-critical systems can profit from such new architectures. To make the potentials of manycore processors usable in safety-critical systems, we devise the operating system MOSSCA that is adapted to the special requirements prevailing in this domain. MOSSCA introduces abstractions that support an application developer in his work of writing safety-critical applications. Internally, MOSSCA runs in a distributed manner to achieve a high parallelism while still guaranteeing a predictable behaviour.

On the Performance and Isolation of Asymmetric Microkernel Design for Lightweight Manycores

“…Several structures for a multikernel OS are possible [17]- [19], but we argue on one that is structured on top of asymmetric microkernel instances. We deliver an open-source implementation of an OS kernel with the aforementioned characteristics and we provide a comprehensive assessment of such design in the Kalray MPPA-256 processor, using a representative benchmark suite.…”

“…Like in MOSSCA [17] and Tessellation [26], Nanvix relies on the clustered organization of the target processors to provide core partitioning and application isolation. However, Nanvix aims lightweight manycores with a distributed memory architecture, which introduces an extra challenge on the resource partitioning algorithms.…”

“…Several designs for a multikernel OS are possible [17]- [19], but we claim that a design that is structured on top of asymmetric microkernel instances better matches the unique architectural features of a lightweight manycore. We argue in favor of this structure due to multiple reasons.…”

Patmos: a time-predictable microprocessor

“…Although not directly covered by the T-CREST project, three real-time operating systems (RTOS) have been ported to Patmos: (1) the Real-Time Executive for Multiprocessor Systems (RTEMS), (2) the time-composable operating system (TiCOS) [7], and (3) the research prototype of MOSSCA [31]. RTEMS is an open source RTOS, popular in avionics.…”

Support for the logical execution time model on a time-predictable multicore processor

“…As hardware we use the Patmos multicore processor [29] from the T-CREST project [27]. We port MOSSCA [21], a research prototype of a manycore operating system for safety-critical applications, to this platform and extend it by communication primitives for the NoC that are mapped into the LET model. The results reported in this paper give a first impression of the costs in terms of memory and execution time that can be expected from such extensions.…”