Will Serverless End the Dominance of Linux in the Cloud?

From the inception of the cloud, running multi-tenant workloads has put strain on the Linux kernel's abstractions. After years of having its abstractions bypassed via virtualization, the kernel has responded with a native container abstraction that is eagerly being applied in the cloud. In this paper, we point out that history is repeating itself: with the introduction of serverless computing, even the native container abstraction is ill-suited. We show that bypassing the kernel with unikernels can yield at least a factor of 6 better latency and throughput. Facing a more complex kernel than ever and a relatively undemanding computing model, we must revisit the question of whether the kernel should try to adapt, we should continue bypassing the kernel, or if it is finally time to try a new native OS for this important future cloud workload.