Recent device hardware trends enable a new approach to the design of network server operating systems. In a traditional operating system, the kernel mediates access to device hardware by server applications, to enforce process isolation as well as network and disk security.We have designed and implemented a new operating system, Arrakis, that splits the traditional role of the kernel in two. Applications have direct access to virtualized I/O devices, allowing most I/O operations to skip the kernel entirely, while the kernel is re-engineered to provide network and disk protection without kernel mediation of every operation.We describe the hardware and software changes needed to take advantage of this new abstraction, and we illustrate its power by showing improvements of 2-5 in latency and 9 in throughput for a popular persistent NoSQL store relative to a well-tuned Linux implementation.
This is a very detailed description of this project in the form of a proper scientific publication, and is part of the Proceedings of the 11th USENIX Symposium on Operating Systems Design and Implementation, accompanied by a presentation. You may want to grab something to drink.