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virtualisation

Hypervisor

Software or firmware that creates and manages virtual machines by abstracting physical hardware resources and arbitrating access between guest operating systems and the underlying CPU, memory, and I/O.

Full Definition

A hypervisor (Virtual Machine Monitor, VMM) enables hardware virtualisation by intercepting guest OS instructions to physical hardware, then emulating or translating them. Two types exist: Type 1 (bare-metal) hypervisors run directly on hardware — VMware ESXi, Microsoft Hyper-V, and Xen — providing lowest overhead. Type 2 (hosted) hypervisors run as an application on a general-purpose OS — VMware Workstation, Oracle VirtualBox — used primarily for development workstations.

Hypervisor technology underpins all major cloud platforms: AWS Nitro (KVM-based), Microsoft Hyper-V, and Google KVM. For AI workloads, PCIe passthrough (SR-IOV) and GPU virtualisation (NVIDIA vGPU and MIG) allow a single GPU to be partitioned across multiple VMs or containers, enabling shared GPU infrastructure in cloud environments. Hypervisor selection is a key architectural decision in enterprise private cloud and managed hosting deployments.

Also Known As

VMMVirtual Machine MonitorESXiKVMHyper V

Source Reference

VMware vSphere Architecture; Microsoft Hyper-V documentation; KVM documentation (kernel.org)

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