api: YAML JSON TOON Database
version: 1.0.0
format: json
dataset:
  slug: virtualization-concepts
  title: Virtualization Concepts
  description: Key concepts in hardware virtualization and virtual machines.
  summary: "The concepts of virtualization: type 1 and type 2 hypervisors, virtual machines, paravirtualization, hardware-assisted virtualization and SR-IOV, plus live migration, snapshots, nested virtualization, ballooning, virtio drivers, device passthrough and thin provisioning."
  use_when[2]: You need to explain how virtual machines share hardware and which techniques improve performance.,You are comparing virtualization with containers.
  caveats[2]: "Virtual machines include a full guest operating system; containers share the host kernel, which changes isolation and overhead.",Feature availability depends on the hypervisor and the hardware.
  related[3]: containerization,cloud-deployment-models,infrastructure-as-code-tools
  category: DevOps
  category_slug: devops
  tags: "devops,virtualization,hypervisor,vm,cloud"
  view_count: 0
  entry_count: 13
  fields[5]{section,field,type,example}:
    data,concept,string,Hypervisor (Type 1)
    data,description,string,Bare-metal hypervisor running directly on hardw…
    data,examples,string,"VMware ESXi, Microsoft Hyper-V, Xen, KVM"
    data,vs,string,"vs Container: heavier isolation, full OS"
    data,benefit,string,Near-native network performance
data[13]:
  - concept: Hypervisor (Type 1)
    description: Bare-metal hypervisor running directly on hardware.
    examples: "VMware ESXi, Microsoft Hyper-V, Xen, KVM"
  - concept: Hypervisor (Type 2)
    description: Hosted hypervisor running on top of a host operating system.
    examples: "VirtualBox, VMware Workstation, Parallels"
  - concept: Virtual Machine
    description: Emulated computer system with its own OS and resources.
    vs: "vs Container: heavier isolation, full OS"
  - concept: Para-virtualization
    description: Guest OS is modified to communicate with hypervisor via hypercalls.
    examples: "Xen (early), IBM LPARs"
  - concept: Hardware-assisted Virtualization
    description: "CPU extensions (Intel VT-x, AMD-V) enable efficient VM isolation."
    examples: Modern hypervisors all use this
  - concept: SR-IOV
    description: Single Root I/O Virtualization - allows direct VM access to PCIe devices.
    benefit: Near-native network performance
  - concept: Live Migration
    description: Moving a running virtual machine between hosts with little or no downtime.
    examples: "VMware vMotion, KVM live migration, Hyper-V Live Migration"
  - concept: Snapshot
    description: A point-in-time capture of a virtual machine's disk and optionally memory state for rollback.
    examples: "VMware snapshots, QEMU/KVM snapshots"
  - concept: Nested Virtualization
    description: Running a hypervisor inside a virtual machine.
    examples: "KVM nested, Hyper-V nested virtualization"
  - concept: Memory Ballooning
    description: A guest driver gives memory back to the host on request so memory can be overcommitted.
    examples: "VMware balloon driver, virtio-balloon"
  - concept: virtio
    description: A standard set of paravirtual device drivers for efficient network and disk I/O in guests.
    examples: "virtio-net, virtio-blk"
  - concept: PCI Passthrough
    description: Giving a guest direct access to a physical device such as a GPU for near-native performance.
    examples: "VFIO, Intel VT-d, AMD-Vi"
  - concept: Thin Provisioning
    description: Allocating virtual disk space only as it is used instead of reserving it all up front.
    examples: "Thin disks in VMware, qcow2 sparse images"