Trends in Operating System Design: Towards a Customisable Persistent Micro-Kernel

Monolithicand micro-kernel-based operating systems such as Unix have failed to provide application developers with sufficient flexibility. They provide a host of inefficient and often inappropriate abstractions that prevent applications from accessing the hardware to exploit efficiency gains. These problems motivated the Grasshopper project to build a new operating system designed to explicitly support orthogonal persistence. Five years on, Grasshopper has demonstrated the feasibility of such an operating system although several problems have been identified. In light of this, we decided to redesign our kernel using modern techniques. This paper examines the trends in operating system design over the last few years and describes our plans to produce a new persistent micro-kernel.