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.

Contents

General

NameCreatorHost CPUGuest CPUHost OSGuest OSLicense
bhyve FreeBSD x86-64 x86, x86-64 FreeBSD, Illumos FreeBSD, FreeNAS, pfSense, OpenBSD, Linux, Windows, Illumos [1] BSD
Bochs Kevin J. LawtonAny x86, x86-64 Windows, Linux, FreeBSD, Unix/X11, Mac OS 9 , macOS, BeOS, MorphOS, OS/2 [2] [3] Windows, Linux, DOS, BSD, OS/2, Haiku LGPL
Containers, or Zones Sun Microsystems x86, x86-64, SPARC (portable: not tied to hardware)Same as host Solaris 10, Solaris 11, OpenSolaris 2009.06, illumos distributions Solaris (8, 9, 10, 11), illumos, Linux (BrandZ) CDDL
Cooperative Linux (coLinux) Dan Aloni, other developersx86Same as hostWindows 2000, XP, 2003, VistaLinux GPL version 2
CHARON Stromasys x86, x86-64 PDP-11, VAX, Alpha, HP3000, SparcWindows, LinuxVMS, OpenVMS, Tru64 UNIX, MPE/iX, RSX-11, RT11, RSTS, Solaris, SunOS Proprietary
Denali University of Washington x86x86Denali Ilwaco, NetBSDNot distributed
DOSBox Peter Veenstra, Sjoerd with communityAnyx86Linux, Windows, classic Mac OS, macOS, BeOS, FreeBSD, NetBSD, OpenBSD, Solaris, QNX, IRIX, MorphOS, AmigaOS, Maemo, SymbianInternally emulated DOS shell; classic PC booter games, unofficially Windows 1.0 to 98 GPL
DOSEMU Community projectx86, x86-64x86LinuxDOS GPL version 2
FreeBSD Jail Poul-Henning Kamp / FreeBSD Any running FreeBSD or DragonFly BSD Same as host FreeBSD, DragonFly BSD same as host (shared *BSD kernel), plus Linux ABI through compat layer BSD
GXemul Anders GavareAny ARM, MIPS, Motorola 88000, PowerPC, SuperH Unix-like NetBSD, OpenBSD, Linux, Ultrix, Sprite BSD
Hercules Roger BowlerAny z/Architecture Windows, FreeBSD, NetBSD, Linux, macOS Linux on IBM Z, z/OS, z/VM, z/VSE, OS/360, DOS/360, DOS/VS, MVS, VM/370, TSS/370 QPL
Hyper-V (2008) Microsoft x86-64 with Intel VT-x or AMD-V x86-64, 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) Microsoft x86-64 with Intel VT-x or AMD-V, ARMv8 [4] x86-64, (up to 64 physical CPUs), ARMv8 Windows 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.
iCore Virtual Accounts iCore Software x86x86Windows XPWindows XP Proprietary
INTEGRITY Green Hills Software ARM, x86, PowerPCSame as hostLinux, Windows INTEGRITY native, Linux, Android, AUTOSAR, Windows (on some platforms) Proprietary
Integrity Virtual Machines Hewlett-Packard IA-64 IA-64 HP-UX HP-UX, Windows, Linux (OpenVMS announced) Proprietary
JPC (Virtual Machine) University of Oxford Any running the Java Virtual Machine x86Java Virtual MachineDOS, Linux, Windows up to 3.0 GPL version 2
KVM Qumranet, now Red Hatx86, x86-64, IA-64, with x86 virtualization, s390, PowerPC, [5] ARM [6] Same as hostLinux, FreeBSD, illumosFreeBSD, Linux, Solaris, Windows, Plan 9 GPL version 2
Linux-VServer Community projectx86, x86-64, IA-64, Alpha, PowerPC 64, PA-RISC 64, SPARC64, ARM, S/390, SH/66, MIPSCompatibleLinuxLinux variants GPL version 2
LynxSecure LynuxWorks x86x86No host OS LynxOS, Linux, Windows Proprietary
LXC Community project, Canonical Ltd. x86, x86-64, IA-64, PowerPC 64, SPARC64, Itanium, ARMSame as hostLinuxLinux variants GPL version 2
OKL4 Microvisor Open Kernel Labs, acquired by General Dynamics Corporation ARM, x86, MIPSARM (v5, v6, v7, v8; paravirtualization), ARMv7VE (hardware virtualization)No Host OSVarious OSes and RTOSes including Linux, Android, QNX Proprietary
OpenVZ Community 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 distribution GPL
Oracle VM Server for x86 Oracle Corporation x86, x86-64x86, x86-64No host OSMicrosoft Windows, Oracle Linux, Red Hat Enterprise Linux, Solaris GPLv2, Oracle VM Server; Manager is proprietary
OVPsim OVPx86OR1K, 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 models Proprietary, Apache 2.0 for models
Parallels Desktop for Mac Parallels, Inc.x86x86, x86-64, aarch64macOSDOS, Windows, Linux, macOS, FreeBSD, OS/2, eComStation, Solaris, Haiku Proprietary
Parallels Workstation (discontinued 2013)Parallels, Inc.x86x86Windows, LinuxWindows, Linux, FreeBSD, OS/2, eComStation, DOS, Solaris, Haiku Proprietary
PearPC Sebastian Biallas x86, x86-64, PowerPCPowerPCWindows, Linux, OS X, FreeBSD, NetBSDMac OS X, Darwin, Linux GPL
PikeOS SYSGO AGPowerPC, x86, ARM, MIPS, SPARC, SuperHSame as hostNo host OS, Linux or Windows as dev. hostsPikeOS native, Linux, POSIX, AUTOSAR, Android, RTEMS, OSEK, ARINC 653 APEX, ITRON Proprietary
Proxmox VE Proxmox x86-64x86, x86-64Debian BasedWindows, Linux, Linux variants, Solaris, FreeBSD, OSx86 (as FreeBSD), virtual appliances, Netware, OS/2, SCO, BeOS, Haiku, Darwin AGPLv3
Oracle VM Server for SPARC (LDoms) Oracle Corporation UltraSPARC T1, UltraSPARC T2, UltraSPARC T2+, SPARC T3, SPARC T4 Compatible Solaris 10, Solaris 11 Oracle support: Solaris; unsupported: Linux, FreeBSD Proprietary
PowerVM IBM POWER4, POWER5, POWER6, POWER7, POWER8, POWER9, Power10 POWER4/5/6/7/8/9/Power10, x86 (PowerVM-Lx86)PowerVM FirmwareLinux PowerPC, x86; AIX, IBM i Proprietary
QEMU Fabrice 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 regularly [7] GPL/LGPL
QEMU w/ kqemu module Fabrice Bellard x86, x86-64Same as hostLinux, FreeBSD, OpenBSD, Solaris, WindowsChanges regularly [7] GPL/LGPL
QEMU w/ qvm86 modulePaul Brookx86x86Linux, NetBSD, WindowsChanges regularly GPL
QuickTransit Transitive Corp. x86, x86-64, IA-64, POWERMIPS, PowerPC, SPARC, x86Linux, OS X, SolarisLinux, OS X, Irix, Solaris Proprietary
RTS Hypervisor Real-Time Systems GmbH x86, x86-64x86, x86-64No host OSWindows, Linux, Windows Embedded, QNX, RTOS-32, VxWorks, OS-9, T-Kernel Proprietary
ScaleMP vSMP FoundationScaleMPx86, x86-64Same as hostNo host OSLinux Proprietary
SIMH Bob Supnik, The Computer History Simulation ProjectAlpha, ARM, HPPA, x86, IA-64, x86-64, M68K, MIPS, MIPSel, POWER, s390, SPARC Data 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 940 BSD, Linux, Solaris, VMS, WindowsDepends on target machine, includes NetBSD/VAX, OpenBSD/VAX, VAX/VMS, Unix v6, Unix v7, TOPS-10, TOPS-20, ITS BSD-like, unique
Simics Virtutech, acquired by Intel x86, 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 others Proprietary
Sun xVM Server Sun Microsystems x86-64, SPARCSame as hostNo host OSWindows XP, 2003 Server (x86-64 only), Linux, Solaris GPL version 3
SVISTA 2004 Serenity Systems International x86x86Windows, OS/2, LinuxWindows, Linux, OS/2, BSD Proprietary
TRANGO TRANGO Virtual Processors, Grenoble, France ARM, XScale, MIPS, PowerPC Paravirtualized ARM, MIPS, PowerPCNo host OS, Linux or Windows as dev. hostsLinux, eCos, µC/OS-II, WindowsCE, Nucleus, VxWorks Proprietary
User Mode Linux Jeff Dike, other developersx86, x86-64, PowerPCSame as hostLinuxLinux GPL version 2
VirtualBox Innotek, acquired by Oracle Corporation x86, x86-64x86, x86-64 (with Intel VT-x or AMD-V, and VirtualBox 2 or later)Windows, Linux, macOS, Solaris, FreeBSD, eComStationDOS, Linux, macOS, [8] 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). [9] GPL 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, Linux Proprietary, some components GPLv2 [10]
Virtual Machine Manager Red Hat x86, x86-64x86, x86-64LinuxLinux, WindowsGPL version 2
Virtual PC 2007 (discontinued) Connectix and Microsoft x86, x86-64x86 Windows 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 2008 Proprietary
Virtual PC 7 for MacConnectix and MicrosoftPowerPCx86Mac OS XWindows, OS/2, Linux Proprietary
VirtualLogix VLXVirtualLogixARM, TI DSP C6000, x86, PowerPCSame as hostNo host OSLinux, Windows XP, C5, VxWorks, Nucleus, DSP/BIOS, proprietary Proprietary
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 Platform CoWare x86, 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, more Proprietary
Virtuozzo SWsoft, now Virtuozzo Inc x86, IA-64, x86-64same as hostLinuxsame as host (shared Linux kernel) Proprietary
vkernel Matthew Dillon / DragonFly BSD x86-64same as host DragonFly BSD any compatible vkernel binary of DragonFly BSD
VMM OpenBSD x86, x86-64same as hostOpenBSDOpenBSD and Linux guests BSD
VMware ESX Server VMware x86, x86-64x86, x86-64No host OSWindows, Linux, Solaris, FreeBSD, OSx86 (as FreeBSD), virtual appliances, Netware, OS/2, SCO, BeOS, Haiku, Darwin, others: runs arbitrary OS [lower-alpha 1] Proprietary
VMware ESXi VMwarex86, x86-64x86, x86-64No host OSSame as VMware ESX Server Proprietary
VMware Fusion VMwarex86, x86-64x86, x86-64macOSSame as VMware ESX Server Proprietary
VMware Server VMwarex86, x86-64x86, x86-64Windows, LinuxSame as VMware ESX Server Proprietary
VMware Workstation VMwarex86-64 [lower-alpha 2] x86, x86-64Windows, LinuxSame as VMware ESX Server Proprietary
VMware Player, later VMware Workstation PlayerVMwarex86-64 [lower-alpha 3] x86, x86-64Windows, LinuxSame as VMware ESX Server Proprietary, free for personal non-commercial use [11] [12]
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 board Proprietary
Xen Xensource, Now Citrix Systems x86, 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 9 GNU GPLv2 +
XCP-ng By 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 9 GNU GPLv2 + [13]
XenServer By Citrix Systems x86, 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 9 GNU GPLv2 +
XtratuM fentISSSPARC v8 LEON2/3/4, ARM v7Same as hostNo host OSGPOS: Linux, RTOS: LithOS, RTEMS Proprietary, GPL version 2 depending on versions
z/VM IBM z/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, predecessors Proprietary
z LPARs IBMz/Architecturez/ArchitectureIntegrated in firmware of System z mainframesLinux on IBM Z, z/OS, z/VSE, z/TPF, z/VM, MUSIC/SP, and predecessors Proprietary
NameCreatorHost CPUGuest CPUHost OS(s)Guest OS(s)License

Features

NameGuest OS SMP availableRuns arbitrary OSSupported guest OS drivers Method of operationTypical useSpeed relative to host OSCommercial support available
Containers, or ZonesYes, over 500-way on current systemsNoUses native device drivers Operating system-level virtualization Server 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[ citation needed ] Yes
OpenVZ YesNoCompatible Operating system-level virtualization Virtualized server isolationUp to near native[ citation needed ] Yes
KVM Yes [14] YesYes AMD-V and Intel-VT-x Virtualized server isolation, server/desktop consolidation, software development, cloud computing, other purposesUp to near native[ citation needed ] Yes [15]
Linux-VServer YesNoCompatible Operating system-level virtualization Virtualized server isolation and security, server consolidation, cloud computingUp to near native[ citation needed ] Yes
Oracle VM Server for x86 YesYesYes Paravirtualization and hardware virtualizationServer consolidation and security, enterprise and business deploymentUp to near native[ citation needed ]Yes
Oracle VM Server for SPARC (LDoms)YesYes, but needs porting [16] Yes Paravirtualization and hardware virtualizationServer consolidation and security, enterprise and business deploymentUp to near native[ citation needed ]Yes
OVPsim YesYes?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)[ citation needed ]Yes, with commercial license from Imperas [17]
PikeOS YesYes, but modifications required as paravirtualization is usedYes Paravirtualization Safety and security critical embedded systems.Up to near native[ citation needed ]Yes
ScaleMP vSMP FoundationYes, up to 8,192 CPUs and 64 TB per VM[ citation needed ]YesYes Virtualization Server consolidation, Cloud computing ?Yes
Simics YesYesYesFull 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 ServerYesYesYes Paravirtualization and porting or hardware virtualizationServers, DevelopmentUp to near native[ citation needed ]Yes
SVISTA 2004No???Hobbyist, Developer, Business workstation??
TRANGO YesYes Yes Paravirtualization and porting or hardware virtualizationMob. phone, STB, routers, etc.Near native [ citation needed ]?
User Mode Linux ?Nospecial guest kernel+modules required Porting Developer (as a separate machine for a server or with X11 networking)Non-significantly slower than native (all calls to kernel are proxied)[ citation needed ]?
OKL4 Microvisor YesYes, (either with para-virtualization or HW virtualization)Yes Paravirtualization, Hardware assisted virtualizationMobile, embedded, security, safety critical, networking, legacy OS, etc.Near nativeYes
Oracle VirtualBox YesYesYes Virtualization Business workstation, server consolidation, service continuity, developer, hobbyistUp to near native[ citation needed ]Yes (with commercial license)
Virtual Iron 3.1Yes, up to 8 wayYesYes Native virtualization Server consolidation, service continuity, dev/test ?Yes
Virtual PC 2007NoYesYes Virtualization, guest calls trapping where supportedHobbyist, Developer, Business workstationUp to near native[ citation needed ] with virtual machine additions?
Windows Virtual PC Yes[ citation needed ]YesYes Hardware virtualization Developer, Business workstation, support for Compatibility with Windows XP applicationsUp to near native[ citation needed ] with virtual machine additionsNo
Virtual PC 7 for MacNoYesYes dynamic recompilation (guest calls trapping where supported)Hobbyist, Developer, Business workstationSlow [ citation needed ]?
Virtual Server 2005 R2NoYesYes Virtualization (guest calls trapping where supported)Server, server farmUp to near native with virtual machine additions but slower than with hypervisor due to proxied calls[ citation needed ]?
CoWare Virtual Platform YesYesYes ( 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[ citation needed ].Yes
Virtuozzo YesNoCompatible Operating system-level virtualization Server consolidation, service continuity, disaster recovery, service providersUp to near native[ citation needed ]Yes
VMware ESXi Server 5.5 (vSphere)Yes, add-on, up to 64 wayNoYes Virtualization Server consolidation, service continuity, dev/test, cloud computing, business critical applications, Infrastructure as a Service IaaS Up to near native[ citation needed ]Yes
VMware ESX Server 4.0 (vSphere)Yes, add-on, up to 8 wayYesYes Virtualization Server consolidation, service continuity, dev/test, cloud computingUp to near native[ citation needed ]Yes
VMware ESX Server 3.0Yes, add-on, up to 4 wayYesYes Virtualization Server consolidation, service continuity, dev/testUp to near native[ citation needed ]Yes
VMware ESX Server 2.5.3Yes, add-on, 2 wayYesYes Virtualization Server consolidation, service continuity, dev/testUp to near native[ citation needed ]Yes
VMware Fusion YesYesYesVirtualizationHobbyist, Developer, Tester, Business workstationUp to near native[ citation needed ]Yes
VMware Server Yes (2-way)YesYes Virtualization Server/desktop consolidation, dev/testUp to near native[ citation needed ]Yes
VMware Workstation Yes (2-way)YesYes Paravirtualization (VMI) and virtualization Technical professional, advanced dev/test, trainerUp to near native[ citation needed ]Yes
VMware Player Yes [18] YesYes Virtualization Technical professional, advanced dev/test, trainer, end user on prebuilt machinesUp to near native[ citation needed ]No
Xen Yes, v4.0.0: up to 128 VCPUs per VMYesYes Paravirtualization 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 native [19] Yes
XCP-ngYesYesYes Paravirtualization and porting or hardware virtualizationVirtualized server isolation, server/desktop consolidation, software development, cloud computing, desktop virtualization, public cloud services, hostings services and other purposes.Up to native[ citation needed ]Yes
XenServer YesYesYes Paravirtualization 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 native [19] Yes
XtratuM YesNoYes Paravirtualization Embedded, safety critical, secureNear to native[ citation needed ]Yes
z/VM Yes, 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 Yes
z LPARs Yes, both real and virtual (guest perceives more CPUs than installed), incl. dynamic CPU provisioning and reassignment; up to 64 real coresYesYes, but not required Microcode and hardware hypervisorServersNative: System z machines always run with at least one LPARYes
NameGuest OS SMP availableRuns arbitrary OSSupported guest OS drivers Method of operationTypical useSpeed relative to host OSCommercial support available

Image type compatibility

Name floppy ISO folders 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)
Bochs [21] YesYesYesYesYesYesNoNoNoNoYesYesNov3, v4
Containers, or Zones ??????????????
Cooperative Linux (coLinux)??????????????
CHARON ??????????????
Denali ??????????????
DOSBox YesYesYesYesYes?NoNoDOSBox-X forkNoNoNoNoNo
DOSEMU ??Yes???????????
FreeBSD Jail NoNoYesNoNoNoNoNoNoNoNoNoNoNo
GXemul ?Yes????????????
Hercules ??????????????
Hyper-V (2008 R2)YesYesNoYesNoNoNoNoNoNoNoYesNoNo
Hyper-V (2012)YesYesNoYesNoNoNoNoNoNoNoYesYesNo
Hyper-V (2012 R2)YesYesNoYesNoNoNoNoNoNoNoYesYesNo
iCore Virtual Accounts ??????????????
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???????
PearPC NoYesNoYesYesNoNoNoNoNoNoNoNoNo
PikeOS ??????????????
PowerVM ??????????????
QEMU YesYesYesYesYesYesread-onlyYesYesYesYesYesexcept difference typeYes
QEMU w/ kqemu module???????YesNoNo????
QEMU w/ qvm86 module???YesYes??YesYes????Yes
QuickTransit ??????????????
ScaleMP vSMP Foundation??????????????
SIMH ??????????????
Simics ??????????????
Sun xVM Server??????????????
SVISTA 2004??????????????
TRANGO ??????????????
User Mode Linux ??????????????
VirtualBox YesYesWith guest integration installed on guest os.Yes [22] Yes [22] Yes [22] up to v2Yesread-onlyYesYesYesCan read existing disks, but not create new disks.Yes
Virtual Iron 3.1??????????????
Virtual PC 2007YesYes????NoNoNoNoNoYesNoNo
Windows Virtual PC YesYes????NoNoNoNoNoYesYesNo
Virtual PC 7 for MacYesYesNoNoNoNoNoNoNoNoNoYesNoNo
VirtualLogix VLX??????????????
Virtual Server 2005 R2??????????????
Synopsys (CoWare) Virtual Platform ??????????????
Virtuozzo ??????????????
VMware ESX Server ???????????Yes??
VMware ESXi YesYesNoYesNoNoNoNoNoNoNoNoNoYes
VMware Fusion ?Yes???????????Yes
VMware Server ?????????????Yes
VMware Workstation YesYes?Yes?????????Yes
VMware Player YesYes?Partial?????????Yes
Wind River Hypervisor??????????????
Wind River VxWorks MILS Platform??????????????
Xen YesYes?YesYes [23] ??Yes [23] Yes [23] ??Yes [23] ??
XCP-ng?Yes?Yes???????YesNo?
XenServer YesYes?YesYes [23] ??Yes [23] Yes [23] ??Yes [23] ??
XtratuM ??????????????
z/VM ??????????????
z LPARs ??????????????
Name floppy ISO folders 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 acceleration Snapshots per VMSnapshot of running systemLive migrationShared foldersShared clipboardPCI passthrough
KVM YesYesYes [24] YesYes (via AIGLX)YesYes [25] Yes [26] Yes
User Mode Linux YesNoNoNoNoNoYesN/A
Containers, or Zones YesYesYesYesNot neededYes [27] YesNoYesNot neededNot needed
DosBox NoNoSVN builds onlyNoGlide (SVN builds only)NoYesNoNoNoNo
Oracle VirtualBox (formerly OSE, GPLv2), with Guest Additions (GPLv2) [28] YesYesYesYesYesYes branched [29] YesYeswith Guest Additions [30] with Guest Additions [30] No
Oracle VirtualBox with Extension Pack (PUEL) and Guest Additions (GPLv2) [28] YesYesYesYesOpenGL 2.0 and Direct3D 8/9 [31] Yes branched [29] YesYesYesYesRetired (Until 6.0; [32] Linux only [33] )
Oracle VM Server for SPARC (LDoms)YesUSB 2.0YesYesNoYesNoYesYesNoYes
OKL4 Microvisor YesYesVMs onlyYesYesNoStatic assignment
Virtual Iron 4.2Yes
Virtual PC 2007NoNoYesNoNoNoYesYes
Windows Virtual PC NopartiallyYesNoNoNoYesYes
VirtualPC 7 for MacNoYesYesYesNoNoYesYes
Microsoft Virtual Server 2005 R2NoYesNoNo ?YesNo
Microsoft Hyper-V Server 2008 R2YesPartial support over remote desktop connections YesYesDirectX 9.0c (via RemoteFX)Yes branchedYesYesNo
Microsoft Hyper-V Server 2012 R2YesYesYesYesDirectX 9.0c (via RemoteFX)Yes branchedYesYesNo
Virtuozzo YesYesYesYesNoYes
VMware ESX Server 3.0 atpYesNo ?YesYesNo
VMware ESX Server 2.5.3YesNoNo
VMware ESX Server 4.0 – 6.x (vSphere)YesYesYesYesYesYesYesYesNoNoYes [34]
VMware Fusion 2.0YesYesYesNo DirectX 9 Shader model 2NoNo
VMware Server YesYesYesYesNo 1 YesNoYesYes
VMware Workstation 5.5YesYesYesYesExperimental support for DirectX 8; also supported with VMGL [35] Yes branchedYesNoYesYesNo
VMware Workstation 6.0YesYesYesYesExperimental support for DirectX 8; Also supported with VMGL [35] Yes branchedYesNoYesYesNo
VMware Workstation 7.0 and 8.0YesYesYesYesSupport for DirectX 9.0c Shader Model 3 and OpenGL 2.13D. [36] Yes branchedYesNoYesYesNo
VMware Player YesYesYesYessupported with VMGL [35] NoNoNoYesNo
Wind River hypervisorYesYesYesYesYesNo
Wind River VxWorks MILS PlatformYes
Xen YesYes [37] Yes [24] YesSupported with VMGL [35]  ?YesYesYes
XCP-ngYesYesYesYesYesYes
XenServer YesYes [24] YesSupported with VMGL [35] YesYesYesYes
z/VM YesNot applicableYes (zURM/HMC)YesNot applicableYes (2011)Not applicableNot applicable
z LPARs YesNot 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

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 Zones No theoretical limit (largest SPARC has 384 physical cores)32 TB (largest SPARC)No limit8191No limitNo limitNo limitNo limit
VMware Player 15.0 [41] No limitNo limitNo limitNo limit164 GB (32-bit); 64 GB (64-bit) ?8 TB
VMware vSphere Hypervisor (ESXi 4.1) [42] 160 logical cores1 TB2 TB minus 512 bytes3208255 GB4 IDE; 60 SCSI2 TB minus 512 bytes
VMware vSphere Hypervisor (ESXi 5.0) [43] 160 logical cores2 TB64 TB512321 TB4 IDE; 60 SCSI2 TB minus 512 bytes
VMware vSphere Hypervisor (ESXi 5.5) (free) [44] 16 NUMA Nodes / 320 logical CPUs4 TBDepending on filesystem51281 TB4 IDE; 60 SCSI; 120 SATA62 TB
VMware vSphere Hypervisor (ESXi 5.5) [45] 16 NUMA Nodes / 320 logical CPUs4 TBDepending on filesystem512641 TB4 IDE; 60 SCSI; 120 SATA62 TB
VMware vSphere Hypervisor (ESXi 6.7) [46] 16 NUMA Nodes / 768 logical CPUs16 TBDepending on filesystem10242566128 GB4 IDE; 256 SCSI; 120 SATA; 60 NVMe62 TB
VMware vSphere Hypervisor (ESXi 7.0) [47] 16 NUMA Nodes / 896 logical CPUs24 TBDepending on filesystem102476824 TB4 IDE; 256 SCSI; 120 SATA; 60 NVMe62 TB
VirtualBox No limitNo limitNo limitNo limit [48] 32No limit4 IDE; no limit for SATA, SCSI, SASGUI: 2 TB
Command line: no limit
Microsoft Hyper-V Server 2008 R2 [49] 64 cores / 8 CPUs [50] 1 TBNo limit384464 GB4 IDE; 256 SCSI2 TB
Microsoft Hyper-V Server 2012 [51] 320 cores / 64 CPUs [52] 4 TBNo limit1024641 TB4 IDE; 256 SCSI64 TB
Microsoft Hyper-V Server 2016 [53] 512 cores / 320 CPUs24 TBNo limit102424012 TB4 IDE; 256 SCSI64 TB
Xen [54]
XCP-ng
Xen Server [54]
4095 CPUsx86
8 CPUsARM32
128 CPUsARM64
16 TBx86
16 GBARM32
5 TBARM64
No limitNo limit512 PVx86 / 128 HVMx86
8ARM32
128ARM64
>1 TB PVx86 / 1 TB HVMx86
16 GBARM32
1 TBARM64
 ? ?
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

  1. Can run a guest OS without modifying it, and hence is generally able to run any OS that could run on a physical machine the VM simulates.
  2. Older versions of VMware Workstation support x86.
  3. Older versions of VMware Player/VMware Workstation Player support x86.

Related Research Articles

In computing, a virtual machine (VM) is the virtualization or emulation of a computer system. Virtual machines are based on computer architectures and provide the functionality of a physical computer. Their implementations may involve specialized hardware, software, or a combination of the two. Virtual machines differ and are organized by their function, shown here:

<span class="mw-page-title-main">Xen</span> Type-1 hypervisor

Xen is a free and open-source type-1 hypervisor, providing services that allow multiple computer operating systems to execute on the same computer hardware concurrently. It was originally developed by the University of Cambridge Computer Laboratory and is now being developed by the Linux Foundation with support from Intel, Citrix, Arm Ltd, Huawei, AWS, Alibaba Cloud, AMD, Bitdefender and epam.

A hypervisor, also known as a virtual machine monitor (VMM) or virtualizer, is a type of computer software, firmware or hardware that creates and runs virtual machines. A computer on which a hypervisor runs one or more virtual machines is called a host machine, and each virtual machine is called a guest machine. The hypervisor presents the guest operating systems with a virtual operating platform and manages the execution of the guest operating systems. Unlike an emulator, the guest executes most instructions on the native hardware. Multiple instances of a variety of operating systems may share the virtualized hardware resources: for example, Linux, Windows, and macOS instances can all run on a single physical x86 machine. This contrasts with operating-system–level virtualization, where all instances must share a single kernel, though the guest operating systems can differ in user space, such as different Linux distributions with the same kernel.

In computing, paravirtualization or para-virtualization is a virtualization technique that presents a software interface to the virtual machines which is similar, yet not identical, to the underlying hardware–software interface.

<span class="mw-page-title-main">QEMU</span> Free virtualization and emulation software

QEMU is a free and open-source emulator. It emulates a computer's processor through dynamic binary translation and provides a set of different hardware and device models for the machine, enabling it to run a variety of guest operating systems. It can interoperate with Kernel-based Virtual Machine (KVM) to run virtual machines at near-native speed. QEMU can also do emulation for user-level processes, allowing applications compiled for one architecture to run on another.

Microsoft Virtual Server was a virtualization solution that facilitated the creation of virtual machines on the Windows XP, Windows Vista and Windows Server 2003 operating systems. Originally developed by Connectix, it was acquired by Microsoft prior to release. Virtual PC is Microsoft's related desktop virtualization software package.

In computing, hardware-assisted virtualization is a platform virtualization approach that enables efficient full virtualization using help from hardware capabilities, primarily from the host processors. A full virtualization is used to emulate a complete hardware environment, or virtual machine, in which an unmodified guest operating system effectively executes in complete isolation. Hardware-assisted virtualization was added to x86 processors in 2005, 2006 and 2010 (respectively).

The following is a timeline of virtualization development. In computing, virtualization is the use of a computer to simulate another computer. Through virtualization, a host simulates a guest by exposing virtual hardware devices, which may be done through software or by allowing access to a physical device connected to the machine.

<span class="mw-page-title-main">VMware ESXi</span> Enterprise-class, type-1 hypervisor for deploying and serving virtual computers

VMware ESXi is an enterprise-class, type-1 hypervisor developed by VMware, a subsidiary of Broadcom, for deploying and serving virtual computers. As a type-1 hypervisor, ESXi is not a software application that is installed on an operating system (OS); instead, it includes and integrates vital OS components, such as a kernel.

<span class="mw-page-title-main">Kernel-based Virtual Machine</span> Virtualization module in the Linux kernel

Kernel-based Virtual Machine (KVM) is a free and open-source virtualization module in the Linux kernel that allows the kernel to function as a hypervisor. It was merged into the mainline Linux kernel in version 2.6.20, which was released on February 5, 2007. KVM requires a processor with hardware virtualization extensions, such as Intel VT or AMD-V. KVM has also been ported to other operating systems such as FreeBSD and illumos in the form of loadable kernel modules.

<span class="mw-page-title-main">VirtualBox</span> Open-source x86 virtualization application

Oracle VM VirtualBox is a hosted hypervisor for x86 virtualization developed by Oracle Corporation. VirtualBox was originally created by InnoTek Systemberatung GmbH, which was acquired by Sun Microsystems in 2008, which was in turn acquired by Oracle in 2010.

<span class="mw-page-title-main">Hyper-V</span> Native hypervisor by Microsoft

Microsoft Hyper-V, codenamed Viridian, and briefly known before its release as Windows Server Virtualization, is a native hypervisor; it can create virtual machines on x86-64 systems running Windows. Starting with Windows 8, Hyper-V superseded Windows Virtual PC as the hardware virtualization component of the client editions of Windows NT. A server computer running Hyper-V can be configured to expose individual virtual machines to one or more networks. Hyper-V was first released with Windows Server 2008, and has been available without additional charge since Windows Server 2012 and Windows 8. A standalone Windows Hyper-V Server is free, but has a command-line interface only. The last version of free Hyper-V Server is Hyper-V Server 2019, which is based on Windows Server 2019.

Sun xVM was a product line from Sun Microsystems that addressed virtualization technology on x86 platforms. One component was discontinued before the Oracle acquisition of Sun; the remaining two continue under Oracle branding.

Oracle VM Server for x86 is the server virtualization offering from Oracle Corporation. Oracle VM Server for x86 incorporates the free and open-source Xen hypervisor technology, supports Windows, Linux, and Solaris guests and includes an integrated Web based management console. Oracle VM Server for x86 features fully tested and certified Oracle Applications stack in an enterprise virtualization environment.

Live migration, also called migration, refers to the process of moving a running virtual machine (VM) or application between different physical machines without disconnecting the client or application. Memory, storage, and network connectivity of the virtual machine are transferred from the original guest machine to the destination. The time between stopping the VM or application on the source and resuming it on destination is called 'downtime'. When the downtime of a VM during live migration is small enough that it is not noticeable by the end user, it is called a 'seamless' live migration.

libvirt Management tool

libvirt is an open-source API, daemon and management tool for managing platform virtualization. It can be used to manage KVM, Xen, VMware ESXi, QEMU and other virtualization technologies. These APIs are widely used in the orchestration layer of hypervisors in the development of a cloud-based solution.

Microsoft RemoteFX is a Microsoft brand name that covers a set of technologies that enhance visual experience of the Microsoft-developed remote display protocol Remote Desktop Protocol (RDP). RemoteFX was first introduced in Windows Server 2008 R2 SP1 and is based on intellectual property that Microsoft acquired and continued to develop since acquiring Calista Technologies. It is a part of the overall Remote Desktop Services workload.

Second Level Address Translation (SLAT), also known as nested paging, is a hardware-assisted virtualization technology which makes it possible to avoid the overhead associated with software-managed shadow page tables.

In computer security, virtual machine escape is the process of a program breaking out of the virtual machine on which it is running and interacting with the host operating system. A virtual machine is a "completely isolated guest operating system installation within a normal host operating system". In 2008, a vulnerability in VMware discovered by Core Security Technologies made VM escape possible on VMware Workstation 6.0.2 and 5.5.4. A fully working exploit labeled Cloudburst was developed by Immunity Inc. for Immunity CANVAS. Cloudburst was presented in Black Hat USA 2009.

GPU virtualization refers to technologies that allow the use of a GPU to accelerate graphics or GPGPU applications running on a virtual machine. GPU virtualization is used in various applications such as desktop virtualization, cloud gaming and computational science.

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