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Comparison of platform virtualization software
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Platform virtualization software, specifically emulators and hypervisors, are software packages that emulate the whole physical computer machine, often providing multiple virtual machines on one physical platform. The table below compares basic information about platform virtualization hypervisors.

General

NameCreatorHost CPUGuest CPUHost OSGuest OSLicense
86BoxMiran Grčax86, x86-64, ARMv7, AArch64x86 (Intel 8086 to Pentium II and compatible)Windows, LinuxWindows, Linux, DOS, BSD, OS/2, HaikuGPL version 3
bhyveFreeBSDx86-64x86, x86-64FreeBSD, IllumosFreeBSD, FreeNAS, pfSense, OpenBSD, Linux, Windows, Illumos1BSD
BochsKevin J. LawtonAnyx86, x86-64Windows, Linux, FreeBSD, Unix/X11, Mac OS 9, macOS, BeOS, MorphOS, OS/223Windows, Linux, DOS, BSD, OS/2, HaikuLGPL
Containers, or ZonesSun Microsystemsx86, x86-64, SPARC (portable: not tied to hardware)Same as hostSolaris 10, Solaris 11, OpenSolaris 2009.06, illumos distributionsSolaris (8, 9, 10, 11), illumos, Linux (BrandZ)CDDL
Cooperative Linux (coLinux)Dan Aloni, other developersx86Same as hostWindows 2000, XP, 2003, VistaLinuxGPL version 2
CHARONStromasysx86, x86-64PDP-11, VAX, Alpha, HP3000, SparcWindows, LinuxVMS, OpenVMS, Tru64 UNIX, MPE/iX, RSX-11, RT11, RSTS, Solaris, SunOSProprietary
DenaliUniversity of Washingtonx86x86DenaliIlwaco, NetBSDNot distributed
DOSBoxPeter Veenstra, Sjoerd with communityAnyx86Linux, Windows, classic Mac OS, macOS, BeOS, FreeBSD, NetBSD, OpenBSD, Solaris, QNX, IRIX, MorphOS, AmigaOS, Maemo, SymbianInternally emulated MS-DOS shell; self-booting disks, unofficially Windows 1.0 to 98GPL
DOSEMUCommunity projectx86, x86-64x86LinuxDOSGPL version 2
FreeBSD JailPoul-Henning Kamp / FreeBSDAny running FreeBSD or DragonFly BSDSame as hostFreeBSD, DragonFly BSDsame as host (shared *BSD kernel), plus Linux ABI through compat layerBSD
GXemulAnders GavareAnyARM, MIPS, Motorola 88000, PowerPC, SuperHUnix-likeNetBSD, OpenBSD, Linux, Ultrix, SpriteBSD
HerculesRoger BowlerAnyz/ArchitectureWindows, FreeBSD, NetBSD, Linux, macOSLinux on IBM Z, z/OS, z/VM, z/VSE, OS/360, DOS/360, DOS/VS, MVS, VM/370, TSS/370QPL
Hyper-V (2008)Microsoftx86-64 with Intel VT-x or AMD-Vx86-64, x86 (up to 8 physical CPUs)Windows Server 2008 (R2) w/Hyper-V role, Microsoft Hyper-V ServerSupported drivers for Windows 2000, Windows 2003, Windows 2008, Windows XP, Windows Vista, FreeBSD, Linux (SUSE 10 released, more announced)Proprietary
Hyper-V (2012+)Microsoftx86-64 with Intel VT-x or AMD-V, ARMv84x86-64, (up to 64 physical CPUs), ARMv8Windows 8, 8.1, 10, and Windows Server 2012 (R2) w/Hyper-V role, Microsoft Hyper-V ServerSupported drivers for Windows NT, FreeBSD, Linux (SUSE 10, RHEL 6, CentOS 6)Proprietary. Component of various Windows editions.
INTEGRITYGreen Hills SoftwareARM, x86, PowerPCSame as hostLinux, WindowsINTEGRITY native, Linux, Android, AUTOSAR, Windows (on some platforms)Proprietary
Integrity Virtual MachinesHewlett-PackardIA-64IA-64HP-UXHP-UX, Windows, Linux (OpenVMS announced)Proprietary
JPC (Virtual Machine)University of OxfordAny running the Java Virtual Machinex86Java Virtual MachineDOS, Linux, Windows up to 3.0GPL version 2
KVMQumranet, now Red Hatx86, x86-64, IA-64, with x86 virtualization, s390, PowerPC,5 ARM6Same as hostLinux, illumosFreeBSD, Linux, Solaris, Windows, Plan 9GPL version 2
Linux-VServerCommunity projectx86, x86-64, IA-64, Alpha, PowerPC 64, PA-RISC 64, SPARC64, ARM, S/390, SH/66, MIPSCompatibleLinuxLinux variantsGPL version 2
LynxSecureLynuxWorksx86x86No host OSLynxOS, Linux, WindowsProprietary
LXCCommunity project, Canonical Ltd.x86, x86-64, IA-64, PowerPC 64, SPARC64, Itanium, ARMSame as hostLinuxLinux variantsGPL version 2
OKL4 MicrovisorOpen Kernel Labs, acquired by General Dynamics CorporationARM, x86, MIPSARM (v5, v6, v7, v8; paravirtualization), ARMv7VE (hardware virtualization)No Host OSVarious OSes and RTOSes including Linux, Android, QNXProprietary
OpenVZCommunity project, supported by SWsoft, now Parallels, Inc.x86, x86-64, IA-64, PowerPC 64, SPARC64Same as hostLinuxsame as host (shared Linux kernel), choice of userland distributionGPL
Oracle VM Server for x86Oracle Corporationx86, x86-64x86, x86-64No host OSMicrosoft Windows, Oracle Linux, Red Hat Enterprise Linux, SolarisGPLv2, Oracle VM Server; Manager is proprietary
OVPsimOVPx86OR1K, MIPS32, ARC600/700, ARM; and public API which enables users to write custom processor models, RISC, CISC, DSP, VLIW all possibleMicrosoft Windows, LinuxDepends on target machine, for example includes MIPS Malta that runs Linux or SMP-Linux; and includes public API which enables users to write custom peripheral and system modelsProprietary, Apache 2.0 for models
Parallels Desktop for MacParallels, Inc.x86x86, x86-64, aarch64macOSDOS, Windows, Linux, macOS, FreeBSD, OS/2, eComStation, Solaris, HaikuProprietary
Parallels Workstation (discontinued 2013)Parallels, Inc.x86x86Windows, LinuxWindows, Linux, FreeBSD, OS/2, eComStation, DOS, Solaris, HaikuProprietary
PearPCSebastian Biallasx86, x86-64, PowerPCPowerPCWindows, Linux, OS X, FreeBSD, NetBSDMac OS X, Darwin, LinuxGPL
PikeOSSYSGOPowerPC, x86, ARM, MIPS, SPARC, RISC-VSame as hostNo host OS, Linux or Windows as dev. hostsPikeOS native, Linux, ELinOS, Windows, POSIX, AUTOSAR, Android, RTEMS, OSEK, ARINC 653 APEX, ITRONProprietary
Proxmox VEProxmoxx86-64x86, x86-64Debian BasedWindows, Linux, Linux variants, Solaris, FreeBSD, OSx86 (as FreeBSD), virtual appliances, Netware, OS/2, SCO, BeOS, Haiku, DarwinAGPLv3
Oracle VM Server for SPARC (LDoms)Oracle CorporationUltraSPARC T1, UltraSPARC T2, UltraSPARC T2+, SPARC T3, SPARC T4CompatibleSolaris 10, Solaris 11Oracle support: Solaris; unsupported: Linux, FreeBSDProprietary
PowerVMIBMPOWER4, POWER5, POWER6, POWER7, POWER8, POWER9, Power10POWER4/5/6/7/8/9/Power10, x86 (PowerVM-Lx86)PowerVM FirmwareLinux PowerPC, x86; AIX, IBM iProprietary
QEMUFabrice Bellard, other developersx86, x86-64, IA-64, PowerPC, SPARC 32/64, ARM, S/390, MIPSx86, x86-64, Alpha, ARM, CRIS, LM32, M68k, MicroBlaze, MIPS, OpenRisc32, PowerPC, S/390, SH4, SPARC 32/64, Unicore32, XtensaWindows, Linux, macOS, Solaris, FreeBSD, OpenBSD, BeOSChanges regularly7GPL/LGPL
QEMU w/ kqemu moduleFabrice Bellardx86, x86-64Same as hostLinux, FreeBSD, OpenBSD, Solaris, WindowsChanges regularly8GPL/LGPL
QEMU w/ qvm86 modulePaul Brookx86x86Linux, NetBSD, WindowsChanges regularlyGPL
QuickTransitTransitive Corp.x86, x86-64, IA-64, POWERMIPS, PowerPC, SPARC, x86Linux, OS X, SolarisLinux, OS X, Irix, SolarisProprietary
RTS HypervisorReal-Time Systems GmbHx86, x86-64x86, x86-64No host OSWindows, Linux, Windows Embedded, QNX, RTOS-32, VxWorks, OS-9, T-KernelProprietary
SIMHBob Supnik, The Computer History Simulation ProjectAlpha, ARM, HPPA, x86, IA-64, x86-64, M68K, MIPS, MIPSel, POWER, s390, SPARCData General Nova, Eclipse; Digital Equipment Corporation PDP-1, PDP-4, PDP-7, PDP-8, PDP-9, PDP-10, PDP-11, PDP-15, VAX; GRI Corporation GRI-909; IBM 1401, 1620, 1130, 7090/7094, System/3; Interdata (Perkin-Elmer) 16b/32b systems; Hewlett-Packard 2114, 2115, 2116, 2100, 21MX; Honeywell H316/H516; MITS Altair 8800 with 8080 and Z80; Royal McBee LGP-30, LGP-21; Scientific Data Systems SDS 940BSD, Linux, Solaris, VMS, WindowsDepends on target machine, includes NetBSD/VAX, OpenBSD/VAX, VAX/VMS, Unix v6, Unix v7, TOPS-10, TOPS-20, ITSBSD-like, unique
SimicsVirtutech, acquired by Intelx86, x86-648051, 68000, ARM (v4, v5, v6, v7), MIPS32, MIPS64, Cavium cnMIPS, Broadcom XLR MIPS, Freescale (e300, e500, e600, e5500, e6500), IBM (POWER, PPC44x, PPC46x, 47x), SPARC v8 (LEON), SPARC v9 (UltraSparc), x86 (from 80286 to Sandy Bridge), x86-64 (from Pentium4 to Sandy Bridge), TI TMS320C64xx, Renesas H8, Renesas SHWindows 32-bit and 64-bit, Linux 32-bit and 64-bitDepends on target machine, typically runs unmodified software stacks from the corresponding real target, including VxWorks, VxWorks 653, OSE, QNX, Linux, Solaris, Windows, FreeBSD, RTEMS, TinyOS, Wind River Hypervisor, VMware ESX, and othersProprietary
Sun xVM ServerSun Microsystemsx86-64, SPARCSame as hostNo host OSWindows XP, 2003 Server (x86-64 only), Linux, SolarisGPL version 3
SVISTA 2004Serenity Systems Internationalx86x86Windows, OS/2, LinuxWindows, Linux, OS/2, BSDProprietary
TRANGOTRANGO Virtual Processors, Grenoble, FranceARM, XScale, MIPS, PowerPCParavirtualized ARM, MIPS, PowerPCNo host OS, Linux or Windows as dev. hostsLinux, eCos, μC/OS-II, WindowsCE, Nucleus, VxWorksProprietary
User Mode LinuxJeff Dike, other developersx86, x86-64, PowerPCSame as hostLinuxLinuxGPL version 2
VirtualBoxInnotek, acquired by Oracle Corporationx86, x86-64x86, x86-64 (with Intel VT-x or AMD-V, and VirtualBox 2 or later)Windows, Linux, macOS, Solaris, FreeBSD, eComStationDOS, Linux, macOS,9 FreeBSD, Haiku, OS/2, Solaris, Syllable, Windows, and OpenBSD (with Intel VT-x or AMD-V, due to otherwise tolerated incompatibilities in the emulated memory management).10GPL version 2; full version with extra enterprise features is proprietary
Virtual Iron 3.1Virtual Iron Software, Inc., acquired by Oraclex86 VT-x, x86-64 AMD-Vx86, x86-64No host OSWindows, LinuxProprietary, some components GPLv211
Virtual Machine ManagerRed Hatx86, x86-64x86, x86-64LinuxLinux, WindowsGPL version 2
Virtual PC 2007 (discontinued)Connectix and Microsoftx86, x86-64x86Windows Vista (Business, Enterprise, Ultimate), XP Pro, XP Tablet PC EditionDOS, Windows, OS/2, Linux (SUSE, Xubuntu), OpenSolaris (Belenix)Proprietary
Windows Virtual PC (discontinued)Connectix and Microsoftx86, x86-64 with Intel VT-x or AMD-Vx86Windows 7Windows XP, Windows Vista, Windows 7, Windows Server 2003, Windows Server 2008Proprietary
Virtual PC 7 for MacConnectix and MicrosoftPowerPCx86Mac OS XWindows, OS/2, LinuxProprietary
VirtualLogix VLXVirtualLogixARM, TI DSP C6000, x86, PowerPCSame as hostNo host OSLinux, Windows XP, C5, VxWorks, Nucleus, DSP/BIOS, proprietaryProprietary
Virtual Server 2005 R2Connectix and Microsoftx86, x86-64x86, x86-64Windows Server 2003, 2008, XP (Requires IIS)Windows NT, 2000, 2003, 2008, Linux (Red Hat, SUSE, Ubuntu)Proprietary
Synopsys (CoWare) Virtual PlatformCoWarex86, x86-64, SPARC v9Devices including (multi) cores from ARM, MIPS, PowerPC, Toshiba MeP, Renesas SH, Texas Instruments, Tensilica, ZSPWindows, Linux, SolarisDepends on guest CPU; includes: Linux (various flavors), μITRON (various flavors), Windows CE, Symbian, moreProprietary
VirtuozzoSWsoft, now Virtuozzo Incx86, IA-64, x86-64same as hostLinuxsame as host (shared Linux kernel)Proprietary
vkernelMatthew Dillon / DragonFly BSDx86-64same as hostDragonFly BSDany compatible vkernel binary of DragonFlyBSD
VMMOpenBSDx86, x86-64same as hostOpenBSDOpenBSD and Linux guestsBSD
VMware ESX ServerVMwarex86, x86-64x86, x86-64No host OSWindows, Linux, Solaris, FreeBSD, OSx86 (as FreeBSD), virtual appliances, Netware, OS/2, SCO, BeOS, Haiku, Darwin, others: runs arbitrary OS12Proprietary
VMware ESXiVMwarex86, x86-64x86, x86-64No host OSSame as VMware ESX ServerProprietary
VMware FusionVMwarex86, x86-64x86, x86-64macOSSame as VMware ESX ServerProprietary
VMware ServerVMwarex86, x86-64x86, x86-64Windows, LinuxSame as VMware ESX ServerProprietary
VMware WorkstationVMwarex86-6413x86, x86-64Windows, LinuxSame as VMware ESX ServerProprietary
VMware Player, later VMware Workstation PlayerVMwarex86-6414x86, x86-64Windows, LinuxSame as VMware ESX ServerProprietary, free for personal non-commercial use1516
Wind River HypervisorWind Riverx86, x86-64, PowerPC, ARMSame as hostNo host OSLinux, VxWorks, unmodified guests (including MS Windows and RTOSes such ach OSE, QNX and others), bare metal virtual boardProprietary
XenXensource, Now Citrix Systemsx86, x86-64, ARM, IA-64 (inactive), PowerPC (inactive)Same as hostLinux, Unix-likeLinux, FreeBSD, MiniOS, NetBSD, Solaris, Windows 7/XP/Vista/Server 2008 (requires Intel VT-x (Vanderpool) or AMD-V (Pacifica)-capable CPU), Plan 9GNU GPLv2 +
XCP-ngBy Vates SASx86, x86-64, ARM, IA-64 (inactive), PowerPC (inactive)Same as hostNo host OSLinux, FreeBSD, MiniOS, NetBSD, Solaris, Windows, Windows Server 2008 (with Intel VT-x or AMD-V), Plan 9GNU GPLv2 +17
XenServerBy Citrix Systemsx86, x86-64, ARM, IA-64 (inactive), PowerPC (inactive)Same as hostNo host OSLinux, FreeBSD, MiniOS, NetBSD, Solaris, Windows 7/XP/Vista/Server 2008 (with Intel VT-x or AMD-V), Plan 9GNU GPLv2 +
XtratuMfentISSSPARC v8 LEON2/3/4, ARM v7Same as hostNo host OSGPOS: Linux, RTOS: LithOS, RTEMSProprietary, GPL version 2 depending on versions
z/VMIBMz/Architecturez/Architecture, z/VM does not run on predecessor mainframesNo host OS, itself (single or multiple levels/versions deep; e.g., VM/ESA running in z/VM 4.4 in z/VM 5.2 in z/VM 5.1.)Linux on IBM Z, z/OS, z/VSE, z/TPF, z/VM, VM/CMS, MUSIC/SP, OpenSolaris for System z, predecessorsProprietary
z LPARsIBMz/Architecturez/ArchitectureIntegrated in firmware of System z mainframesLinux on IBM Z, z/OS, z/VSE, z/TPF, z/VM, MUSIC/SP, and predecessorsProprietary
NameCreatorHost CPUGuest CPUHost OS(s)Guest OS(s)License

Features

NameGuest OS SMP availableRuns arbitrary OSSupported guest OS driversMethod of operationTypical useSpeed relative to host OSCommercial support available
Containers, or ZonesYes, over 500-way on current systemsNoUses native device driversOperating system-level virtualizationServer consolidation with workload isolation, single workload containment, hosting, dev/test/prodNear nativeYes
Hyper-V Server 2008 R2Yes, up to 4 VCPUs per VMYesYesVirtualizationServer consolidation, service continuity, dev/test, desktop virtualization, cloud computingUp to near native[3]Yes
OpenVZYesNoCompatibleOperating system-level virtualizationVirtualized server isolationUp to near native[4]Yes
KVMYes18YesYesAMD-V and Intel-VT-xVirtualized server isolation, server/desktop consolidation, software development, cloud computing, other purposesUp to near native[5]Yes19
Linux-VServerYesNoCompatibleOperating system-level virtualizationVirtualized server isolation and security, server consolidation, cloud computingUp to near native[6]Yes
Oracle VM Server for x86YesYesYesParavirtualization and hardware virtualizationServer consolidation and security, enterprise and business deploymentUp to near nativeYes
Oracle VM Server for SPARC (LDoms)YesYes, but needs porting20YesParavirtualization and hardware virtualizationServer consolidation and security, enterprise and business deploymentUp to near nativeYes
OVPsimYesYes?Full system simulation with optional component virtualizationSoftware development (early, embedded), advanced debug for single and multicore software, compiler and other tool development, computer architecture research, hobbyistDepends on target architecture (full and slow hardware emulation for guests incompatible with host)Yes, with commercial license from Imperas21
PikeOSYesYes, but modifications required as paravirtualization is usedYesParavirtualizationSafety and security critical embedded systems.Up to near nativeYes
SimicsYesYesYesFull system simulation of processors, MMUs, devices, disks, memories, networks, etc.Software development, advanced debug for single and multicore software, compiler and other tool development, computer architecture research, bug transportation, automated testing, system architecture, long-term support of safety-critical systems, early hardware availability, virtual prototypingDepends on host machine and target architecture. Runs at near-native speeds for x86-on-x86 using VT-x, cross-simulation of other architectures can be faster or slower than real-time depending on how fast the target is and how big the target is (number of processors, number of target machines, and how much the simulation can be parallelized)Yes
Sun xVM ServerYesYesYesParavirtualization and porting or hardware virtualizationServers, DevelopmentUp to near nativeYes
SVISTA 2004No???Hobbyist, Developer, Business workstation??
TRANGOYesYes[7]YesParavirtualization and porting or hardware virtualizationMob. phone, STB, routers, etc.Near native[8]?
User Mode Linux?Nospecial guest kernel+modules requiredPortingDeveloper (as a separate machine for a server or with X11 networking)Non-significantly slower than native [9] (all calls to kernel are proxied)?
OKL4 MicrovisorYesYes, (either with para-virtualization or HW virtualization)YesParavirtualization, Hardware assisted virtualizationMobile, embedded, security, safety critical, networking, legacy OS, etc.Near nativeYes
Oracle VirtualBoxYesYesYesVirtualizationBusiness workstation, server consolidation, service continuity, developer, hobbyistUp to near nativeYes (with commercial license)
Virtual Iron 3.1Yes, up to 8 wayYesYesNative virtualizationServer consolidation, service continuity, dev/test?Yes
Virtual PC 2007NoYesYesVirtualization, guest calls trapping where supportedHobbyist, Developer, Business workstationUp to near native with virtual machine additions?
Windows Virtual PCYesYesYesHardware virtualizationDeveloper, Business workstation, support for Compatibility with Windows XP applicationsUp to near native with virtual machine additionsNo
Virtual PC 7 for MacNoYesYesdynamic recompilation (guest calls trapping where supported)Hobbyist, Developer, Business workstationSlow ?
Virtual Server 2005 R2NoYesYesVirtualization (guest calls trapping where supported)Server, server farmUp to near native with virtual machine additions but slower than with hypervisor due to proxied calls?
CoWare Virtual PlatformYesYesYes ( Same compiled Software image as for the real device)Full-system virtualization (Processor Core ISA + Hardware + External connections)Early embedded software development and integration (from driver to application), Multi-core software debugging and optimizationDepending on the system characteristics and the software itself, ranges from faster than real time to slow.Yes
VirtuozzoYesNoCompatibleOperating system-level virtualizationServer consolidation, service continuity, disaster recovery, service providersUp to near nativeYes
VMware ESXi Server 5.5 (vSphere)Yes, add-on, up to 64 wayNoYesVirtualizationServer consolidation, service continuity, dev/test, cloud computing, business critical applications, Infrastructure as a Service IaaSUp to near nativeYes
VMware ESX Server 4.0 (vSphere)Yes, add-on, up to 8 wayYesYesVirtualizationServer consolidation, service continuity, dev/test, cloud computingUp to near nativeYes
VMware ESX Server 3.0Yes, add-on, up to 4 wayYesYesVirtualizationServer consolidation, service continuity, dev/testUp to near nativeYes
VMware ESX Server 2.5.3Yes, add-on, 2 wayYesYesVirtualizationServer consolidation, service continuity, dev/testUp to near nativeYes
VMware FusionYesYesYesVirtualizationHobbyist, Developer, Tester, Business workstationUp to near nativeYes
VMware ServerYes (2-way)YesYesVirtualizationServer/desktop consolidation, dev/testUp to near nativeYes
VMware WorkstationYes (2-way)YesYesParavirtualization (VMI) and virtualizationTechnical professional, advanced dev/test, trainerUp to near nativeYes
VMware PlayerYes22YesYesVirtualizationTechnical professional, advanced dev/test, trainer, end user on prebuilt machinesUp to near nativeNo
XenYes, v4.0.0: up to 128 VCPUs per VMYesYesParavirtualization and porting or hardware virtualizationVirtualized server isolation, server/desktop consolidation, software development, cloud computing, other purposes. Xen powers most public cloud services and many hosting services, such as Amazon Web Services, Rackspace Hosting and Linode.Up to native23Yes
XenServerYesYesYesParavirtualization and porting or hardware virtualizationVirtualized server isolation, server/desktop consolidation, software development, cloud computing, other purposes. Xen powers most public cloud services and many hosting services, such as Amazon Web Services, Rackspace Hosting and Linode.Up to native24Yes
XtratuMYesNoYesParavirtualizationEmbedded, safety critical, secureNear to nativeYes
z/VMYes, both real and virtual (guest perceives more CPUs than installed), incl. dynamic CPU provisioning and reassignmentYesYes, but not requiredVirtualization (among first systems to provide hardware assists)ServersNear native[10]Yes
z LPARsYes, both real and virtual (guest perceives more CPUs than installed), incl. dynamic CPU provisioning and reassignment; up to 64 real coresYesYes, but not requiredMicrocode and hardware hypervisorServersNative: System z machines always run with at least one LPARYes
NameGuest OS SMP availableRuns arbitrary OSSupported guest OS driversMethod of operationTypical useSpeed relative to host OSCommercial support available
  • ^ Providing any virtual environment usually requires some overhead of some type or another. Native usually means that the virtualization technique does not do any CPU level virtualization (like Bochs), which executes code more slowly than when it is directly executed by a CPU. Some other products such as VMware and Virtual PC use similar approaches to Bochs and QEMU, however they use a number of advanced techniques to shortcut most of the calls directly to the CPU (similar to the process that JIT compiler uses) to bring the speed to near native in most cases. However, some products such as coLinux, Xen, z/VM (in real mode) do not suffer the cost of CPU-level slowdowns as the CPU-level instructions are not proxied or executing against an emulated architecture since the guest OS or hardware is providing the environment for the applications to run under. However access to many of the other resources on the system, such as devices and memory may be proxied or emulated in order to broker those shared services out to all the guests, which may cause some slow downs as compared to running outside of virtualization.
  • ^ OS-level virtualization is described as "native" speed, however some groups have found overhead as high as 3% for some operations, but generally figures come under 1%, so long as secondary effects do not appear.
  • ^ See25 for a paper comparing performance of paravirtualization approaches (e.g. Xen) with OS-level virtualization
  • ^ Requires patches/recompiling.
  • ^ Exceptional for lightweight, paravirtualized, single-user VM/CMS interactive shell: largest customers run several thousand users on even single prior models. For multiprogramming OSes like Linux on IBM Z and z/OS that make heavy use of native supervisor state instructions, performance will vary depending on nature of workload but is near native. Hundreds into the low thousands of Linux guests are possible on a single machine for certain workloads.

Image type compatibility

NamefloppyISOfolders on hostphysical disk /deviceraw / flat(whole disk)raw / flat(partition)hdd(Parallels)QCOW(QEMU)QCOW2(QEMU)QED(QEMU)VDI(VirtualBox)VHD(Connectix Virtual PC)VHDX(Hyper-V)VMDK(VMware)
86BoxYesYesCD-ROM drive onlyNoYesNoNoNoNoNoNoYesNoNo
Bochs26YesYesYesYesYesYesNoNoNoNoYesYesNov3, v4
Containers, or Zones??????????????
Cooperative Linux (coLinux)??????????????
CHARON??????????????
Denali??????????????
DOSBoxYesYesYesYesYes?NoNoDOSBox-X forkNoNoNoNoNo
DOSEMU??Yes???????????
FreeBSD JailNoNoYesNoNoNoNoNoNoNoNoNoNoNo
GXemul?Yes????????????
Hercules??????????????
Hyper-V (2008 R2)YesYesNoYesNoNoNoNoNoNoNoYesNoNo
Hyper-V (2012)YesYesNoYesNoNoNoNoNoNoNoYesYesNo
Hyper-V (2012 R2)YesYesNoYesNoNoNoNoNoNoNoYesYesNo
Integrity Virtual Machines??????????????
JPC (Virtual Machine)YesYesYes?Yes?????????
Linux-VServer??????????????
LynxSecure??????????????
LXC??????????????
OpenVZ??????????????
Oracle VM Server for x86??????????????
Oracle VM Server for SPARC (LDoms)??????????????
OVPsim??????????????
Parallels Desktop for Mac??????Yes???????
Parallels Workstation??????Yes???????
PearPCNoYesNoYesYesNoNoNoNoNoNoNoNoNo
PikeOS??????????????
PowerVM??????????????
QEMUYesYesYesYesYesYesread-onlyYesYesYesYesYesexcept difference typeYes
QEMU w/ kqemu module???????YesNoNo????
QEMU w/ qvm86 module???YesYes??YesYes????Yes
QuickTransit??????????????
SIMH??????????????
Simics??????????????
Sun xVM Server??????????????
SVISTA 2004??????????????
TRANGO??????????????
User Mode Linux??????????????
VirtualBoxYesYesWith guest integration installed on guest os.Yes27Yes28Yes29up to v2Yesread-onlyYesYesYesCan read existing disks, but not create new disks.Yes
Virtual Iron 3.1??????????????
Virtual PC 2007YesYes????NoNoNoNoNoYesNoNo
Windows Virtual PCYesYes????NoNoNoNoNoYesYesNo
Virtual PC 7 for MacYesYesNoNoNoNoNoNoNoNoNoYesNoNo
VirtualLogix VLX??????????????
Virtual Server 2005 R2??????????????
Synopsys (CoWare) Virtual Platform??????????????
Virtuozzo??????????????
VMware ESX Server???????????Yes??
VMware ESXiYesYesNoYesNoNoNoNoNoNoNoNoNoYes
VMware Fusion?Yes???????????Yes
VMware Server?????????????Yes
VMware WorkstationYesYes?Yes?????????Yes
VMware PlayerYesYes?Partial?????????Yes
Wind River Hypervisor??????????????
Wind River VxWorks MILS Platform??????????????
XenYesYes?YesYes30??Yes31Yes32??Yes33??
XenServerYesYes?YesYes34??Yes35Yes36??Yes37??
XtratuM??????????????
z/VM??????????????
z LPARs??????????????
NamefloppyISOfolders on hostphysical disk /deviceraw / flat(whole disk)raw / flat(partition)hdd(Parallels)QCOW(QEMU)QCOW2(QEMU)QED(QEMU)VDI(VirtualBox)VHD(Connectix Virtual PC)VHDX(Hyper-V)VMDK(VMware)

Other features

NameCan boot an OS on another disk partition as guestUSB supportGUILive memory allocation3D accelerationSnapshots per VMSnapshot of running systemLive migrationShared foldersShared clipboardPCI passthrough
KVMYesYesYes38YesYes (via AIGLX)YesYes39Yes40Yes
User Mode LinuxYesNoNoNoNoNoYesN/A
Containers, or ZonesYesYesYesYesNot neededYes41YesNoYesNot neededNot needed
DosBoxNoNoSVN builds onlyNoGlide (SVN builds only)NoYesNoNoNoNo
Oracle VirtualBox (formerly OSE, GPLv2), with Guest Additions (GPLv2)42YesYesYesYesYesYes branched43YesYeswith Guest Additions44with Guest Additions45No
Oracle VirtualBox with Extension Pack (PUEL) and Guest Additions (GPLv2)46YesYesYesYesOpenGL 2.0 and Direct3D 8/947Yes branched48YesYesYesYesRetired (Until 6.0;49 Linux only50)
Oracle VM Server for SPARC (LDoms)YesUSB 2.0YesYesNoYesNoYesYesNoYes
OKL4 MicrovisorYesYesVMs onlyYesYesNoStatic assignment
Virtual Iron 4.2Yes
Virtual PC 2007NoNoYesNoNoNoYesYes
Windows Virtual PCNopartiallyYesNoNoNoYesYes
VirtualPC 7 for MacNoYesYesYesNoNoYesYes
Microsoft Virtual Server 2005 R2NoYesNoNo?YesNo
Microsoft Hyper-V Server 2008 R2YesPartial support over remote desktop connections [11]YesYesDirectX 9.0c [12] (via RemoteFX)Yes branchedYesYesNo
Microsoft Hyper-V Server 2012 R2YesYesYesYesDirectX 9.0c [13] (via RemoteFX)Yes branchedYesYesNo
VirtuozzoYesYesYesYesNoYes
VMware ESX Server 3.0 atpYesNo?YesYesNo
VMware ESX Server 2.5.3YesNoNo
VMware ESX Server 4.0 – 6.x (vSphere)YesYesYesYesYesYesYesYesNoNoYes51
VMware Fusion 2.0YesYesYesNoDirectX 9 Shader model 2NoNo
VMware ServerYesYesYesYesNo1YesNoYesYes
VMware Workstation 5.5YesYesYesYesExperimental support for DirectX 8; also supported with VMGL52Yes branchedYesNoYesYesNo
VMware Workstation 6.0YesYesYesYesExperimental support for DirectX 8; Also supported with VMGL53Yes branchedYesNoYesYesNo
VMware Workstation 7.0 and 8.0YesYesYesYesSupport for DirectX 9.0c Shader Model 3 and OpenGL 2.13D.54Yes branchedYesNoYesYesNo
VMware PlayerYesYesYesYessupported with VMGL55NoNoNoYesNo
Wind River hypervisorYesYesYesYesYesNo
Wind River VxWorks MILS PlatformYes
XenYesYes56Yes57YesSupported with VMGL58?YesYesYes
XenServerYesYes59YesSupported with VMGL60YesYesYesYes
z/VMYesNot applicableYes (zURM/HMC)YesNot applicableYes (2011)Not applicableNot applicable
z LPARsYesNot applicableYes (HMC)YesNot applicableYes (2007)Not applicableNot applicable
NameCan boot an OS on another disk partition as guestUSBGUILive memory allocation3D accelerationSnapshots per VMSnapshot of running systemLive migrationShared foldersShared clipboardPCI passthrough
  • ^ Windows Server 2008 R2 SP1 and Windows 7 SP1 have limited support for redirecting the USB protocol over RDP using RemoteFX.61
  • ^ Windows Server 2008 R2 SP1 adds accelerated graphics support for certain editions of Windows Server 2008 R2 SP1 and Windows 7 SP1 using RemoteFX.6263

Restrictions

This table is meant to outline restrictions in the software dictated by licensing or capabilities.

NameMaximum host cores / CPUsMaximum host memoryMaximum host disk volume sizeMaximum number of guest VM runningMaximum number of logical CPU per VM guestMaximum amount of memory per VM guestMaximum number of SCSI + IDE disks per VM guestMaximum disk size per VM guest
Containers, or ZonesNo theoretical limit (largest SPARC has 384 physical cores)32 TB (largest SPARC)No limit8191No limitNo limitNo limitNo limit
VMware Player 15.064No limitNo limitNo limitNo limit164 GB (32-bit); 64 GB (64-bit)?8 TB
VMware vSphere Hypervisor (ESXi 4.1)65160 logical cores1 TB2 TB minus 512 bytes3208255 GB4 IDE; 60 SCSI2 TB minus 512 bytes
VMware vSphere Hypervisor (ESXi 5.0)66160 logical cores2 TB64 TB512321 TB4 IDE; 60 SCSI2 TB minus 512 bytes
VMware vSphere Hypervisor (ESXi 5.5) (free)6716 NUMA Nodes / 320 logical CPUs4 TBDepending on filesystem51281 TB4 IDE; 60 SCSI; 120 SATA62 TB
VMware vSphere Hypervisor (ESXi 5.5)6816 NUMA Nodes / 320 logical CPUs4 TBDepending on filesystem512641 TB4 IDE; 60 SCSI; 120 SATA62 TB
VMware vSphere Hypervisor (ESXi 6.7)6916 NUMA Nodes / 768 logical CPUs16 TBDepending on filesystem10242566128 GB4 IDE; 256 SCSI; 120 SATA; 60 NVMe62 TB
VMware vSphere Hypervisor (ESXi 7.0)7016 NUMA Nodes / 896 logical CPUs24 TBDepending on filesystem102476824 TB4 IDE; 256 SCSI; 120 SATA; 60 NVMe62 TB
VirtualBoxNo limitNo limitNo limitNo limit7132No limit4 IDE; no limit for SATA, SCSI, SASGUI: 2 TBCommand line: no limit
Microsoft Hyper-V Server 2008 R27264 cores / 8 CPUs731 TBNo limit384464 GB4 IDE; 256 SCSI2 TB
Microsoft Hyper-V Server 201274320 cores / 64 CPUs754 TBNo limit1024641 TB4 IDE; 256 SCSI64 TB
Microsoft Hyper-V Server 201676512 cores / 320 CPUs24 TBNo limit102424012 TB4 IDE; 256 SCSI64 TB
NameMaximum host cores / CPUsMaximum host memoryMaximum host disk volume sizeMaximum number of guest VM runningMaximum number of logical CPU per VM guestMaximum amount of memory per VM guestMaximum number of SCSI + IDE disks per VM guestMaximum disk size per VM guest

Note: No limit means no enforced limit. For example, a VM with 1 TB of memory cannot fit in a host with only 8 GB memory and no memory swap disk, so it will have a limit of 8 GB physically.

See also

Notes

References

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