A Performance Evaluation of Lightweight Approaches to Virtualization

The growing prevalence of the microservice paradigm has initiated a shift away from operating single image appliances that host many services, towards encapsulating each service within individual, smaller images. As a result thereof, the demand for low-overhead virtualization techniques is increasing. While containerization approaches already enjoy great popularity, unikernels are emerging as alternative approaches. With both approaches undergoing rapid improvements, the current landscape of lightweight approaches to virtualization presents a confusing scenery, impeding the task of picking an adequate technology for an intended purpose. While previous work has mostly dealt with comparing the performance of either approach with whole-system virtualization, this work provides an overarching performance evaluation covering containers, unikernels, wholesystem virtualization, native hardware, and combinations thereof. Representing common workloads in cloud-based applications, we evaluate application performance by the example of HTTP servers and a key-value store. Keywords–Lightweight Virtualization; Performance; Unikernel; Container