Containers & Virtual machines : A performance, resource & power consumption comparison

Abstract: Due to the growth of cloud computing in recent years, the use of virtualization has exploded. Virtual machines (VMs) and containers are both virtualization technologies used to create isolated computing environments. While VMs are created and managed by hypervisors and need their own full guest operating system, containers share the kernel of the host computers and do not need a full guest operating system. Because of this, containers are rumored to have less overhead involved, yielding higher performance and less resource usage compared to VMs.  In this paper we perform a literature study along with an empirical study to examine the differences between containers and virtual machines when it comes to cpu, memory and disk performance, cpu and memory resource utilization, and power consumption. To answer the question regarding performance, a series of benchmarks were run inside both a container and a VM. During these benchmarks the resource utilization of the host machine was also measured to answer the second question and to answer the third and final question the power draw was measured while some of the benchmarks were running. The results showed that the cpu performance was extremely similar between the two and memory performance seemed to be similar for the most part but fairly big differences were seen in favor of both depending on the benchmark in some cases. With disk performance the container was between 15-50% faster depending on the benchmark. As for resource usage, the cpu usage was the same for both technologies but memory usage differed greatly in favor of the container. The VM used between 3-4 GiB and the container between 70 MiB - 2.5 GiB depending on the benchmark. The power draw was the same for both technologies when under cpu and memory load but when idle the VM proved to draw around 40% more power.