Larger Cloud Servers, Fewer Hosts? On the Evolution of VM Sizes in IaaS Platforms

Hardware evolution has been extensively characterized, with models describing long-term trends in processors, storage, and memory. In contrast, the evolution of the virtual resources through which most practitioners interact with computing infrastructure remains largely unexplored. This paper studies how Virtual Machine (VM) configurations have evolved across major cloud providers over the past two decades. Using historical catalogs and large-scale usage traces, we analyze both the supply of VM types and the way clients actually consume them. Our analysis shows that VM evolution diverges from underlying hardware trends. Although provider catalogs have expanded toward larger configurations, client demand remains concentrated on the smallest options. At the same time, larger options are increasingly selected, and gradual increases in minimal allocations have raised the footprint of active VMs, which doubled between 2019 and 2025. Consequently, despite growing hardware capabilities, the number of instances consolidated per host has remained stable over time. These trends have important environmental implications. By progressively inflating default VM footprints, cloud offerings weaken incentives for software efficiency and limit the potential gains from consolidating workloads on more capable servers.