Co-Designing Clusters of Lightweight Manycores and Asymmetric Operating System Kernels

Multikernel operating systems (OSs) were introduced to cope with challenges in software development and deployment in lightweight manycores. Among the possible structures for a multikernel OS, we focus on designs based on asymmetric kernels. This design delivers better performance isolation, but it suffers from an overhead in energy efficiency. In this letter, we overcome this issue with a co-design solution between the cluster of a lightweight manycore and an asymmetric kernel. We designed a 4-core heterogeneous cluster with one core tuned for the OS kernel and we patched the OS kernel to better match the characteristics of this core. Our experiments unveiled that our solution consumes 14.1% less power than the baseline and also improves the OS kernel performance by up to 6.5%.