A virtual machine (VM) is an emulation of a computer system. VMs operate based on computer architectures and provide functionality of a physical computer. Software applications and operating systems can be loaded onto a virtual machine, allowing it to execute programs like a physical device.
The first virtual machine concept was developed in the 1950s and 1960s by scientists at IBM, MIT, and Stanford University. The initial virtual machines were designed to efficiently share expensive mainframe computer hardware while securely separating the different projects and users.
Overview of Virtual Machines
A virtual machine is created within a computing environment referred to as a hypervisor or virtual machine monitor (VMM). This software creates and runs the VMs, allocating hardware resources from the host computer system as needed.
Some key capabilities and benefits of virtual machines include:
- Isolation: VMs operate independently from the host computer system and from other VMs running on the same host. This isolation prevents software conflicts and provides security and data protection.
- Abstraction: The virtual machine hardware is abstracted from the underlying physical hardware, allowing portability across different hosts. This abstraction enables migration to stronger host servers as needed.
- Encapsulation: The VM encapsulates a complete computation environment, including application, libraries, configurations, and operating system, streamlining deployment and testing.
- Hardware independence: Software running inside a VM is hardware agnostic, simplifying development and migration between environments.
First Virtual Machine System Concepts
The earliest virtual machine system concepts focused on effectively sharing expensive mainframe computers between different users and projects in a secure and isolated manner.
Some of the key innovations and capabilities of the first VM systems included:
- Time-sharing: Enabling multiple users to share computer time for more efficient utilization.
- Multiprogramming: Allowing multiple programs to reside in memory for faster switching between tasks.
- Memory and CPU virtualization: Abstracting the underlying hardware to create virtual computation environments.
- Device virtualization: Emulating virtual devices like disks and network adapters to provide IO capabilities.
- VM isolation and security: Securely separating users and resources to prevent interference.
- Hypervisor: A software layer to create, run, monitor, and manage VMs.
History and Origins of Virtual Machines
The early pioneers who developed foundational virtual machine concepts include:
- Christopher Strachey (1962) – First formal description of key VM capabilities at the National Physics Laboratory (NPL) in the U.K.
- IBM M44/44X (1960s) – Mainframe operating system with virtual memory support running in fully isolated virtual machines.
- Fernando J. Corbato and MIT (1960s) – Developed one of the first time-sharing computer systems, known as the Compatible Time-Sharing System (CTSS), which had basic VM capabilities.
- IBM CP-40 (1964) – An experimental mainframe system at IBM’s Cambridge Scientific Center that supported multiprogramming and VM capabilities. This directly inspired IBM’s first official VMM system, CP-67, a few years later.
- Stanford University (1965-1970) – Lawrence Roberts led an advanced research project on a time-sharing system for computer centers. This paved the way for the virtual machine and hypervisor concepts used in modern data centers.
So in summary, virtual machine concepts originated in the late 1950s and 1960s with academia and industry pioneers that needed to safely partition expensive mainframe computer hardware for shared utilization efficiency. Their innovations with time-sharing, virtual memory, and virtual devices set the foundation for today’s enterprise and cloud VMs.
Virtualization in Modern Computing
Virtual machine technology has expanded significantly from the original mainframe systems to become a cornerstone of computing today. Some major developments include:
- IBM VM/370 (1972) – The first official IBM virtual machine architecture built on the concepts proven earlier in experimental systems like CP-40 and CP-67. This evolved into z/VM which is still used extensively on mainframes today.
- Dispatchable virtual machines – VM innovations in the 1980s and 1990s that enabled memory sharing and dynamic resource allocation, improving hardware utilization. This foreshadowed capacity optimizations in modern hypervisors.
- Hardware support for virtualization – CPU instruction set extensions like Intel VT-x (2005) and AMD-V (2006) provided hardware support to accelerate virtualization, enabling performance closer to native speeds.
- Enterprise adoption – VMware led the popularization of virtual infrastructure in the early 2000s as hardware standardization allowed virtualization to move from mainframes to commodity servers. This paved the way for wide enterprise adoption.
- Cloud computing – The isolation, abstraction, and portability benefits of VMs enabled the foundation for cloud services like AWS EC2 which provides scalable on-demand compute capacity by leveraging VMs.
So while virtual machines originated decades ago, ongoing innovation has adapted VM technology to match the evolving hardware landscape while expanding their capabilities and use cases substantially over time. VMs transitioned from solely mainframes to widespread enterprise use and now power the world’s largest cloud platforms as a fundamental building block providing secure, portable compute environments.
Key Takeaways on the First Virtual Machines
- Virtual machines originated in the late 1950s and 1960s when pioneers at organizations like IBM, MIT, and Stanford needed to safely and efficiently partition expensive mainframe hardware.
- By virtualizing resources like memory, CPUs, and devices, the first VMs provided isolated and portable computation environments for early time-sharing and multiprogramming systems.
- Capabilities proven in experimental systems like CP-40 and concepts formalized by Christoper Strachey formed the foundation for official products like IBM VM/370 in 1972.
- Ongoing hardware and software advances have adapted VMs from solely mainframes to widespread enterprise servers and now the global cloud, greatly expanding their capabilities and use cases over time.
- Modern VMs provide portable, secure sandboxed environments enabling computing innovation across personal devices, enterprise data centers, and hyperscale cloud platforms.
In conclusion, the first virtual machine concepts paved the way for the virtualization revolution in computing over recent decades. By abstracting hardware resources to enable portability, isolation, and sharing capabilities, VMs transformed how we architect systems and apply compute power, from mainframes to the mainstream. Virtual machines have proven to be one of the most pivotal innovations that helped computing scale from room-sized early computers to the ubiquitous and vast cloud platforms powering our modern digital world, with innovation ongoing to evolve VMs for the next generation of advancement.
Frequently Asked Questions
- Who invented the first virtual machine?
While no single individual is solely credited with inventing the virtual machine, key pioneers in the 1950s and 1960s include scientists and researchers Christopher Strachey, Bob Creasy, Larry Roberts, and Fernando Corbato who formalized foundational VM concepts at organizations like IBM, MIT, NPL, and Stanford University.
- When was the first working virtual machine created?
The first working experimental virtual machines were created in the mid 1960s on mainframe systems. This includes IBM’s CP-40 system in 1964 and CP-67 in 1967 which eventually inspired the official IBM VM/370 virtual machine architecture released in 1972.
- What was the first commercial virtual machine?
IBM’s VM/370 platform launched in 1972 is considered the first mainstream commercial virtual machine offering. It enabled multitasking of mainframe environments using virtual memory, virtual CPUs, and isolation between virtual machines.
- What hardware component allowed virtual machines?
Virtual machines were enabled in the 1960s after the introduction of hardware capabilities like memory and CPU virtualization, interrupts, time-sharing, and multiprogramming support. This provided the building blocks to abstract and slice physical hardware into isolated virtual environments.
- Why were virtual machines originally created?
The original goal was efficiently and securely partitioning expensive mainframe systems between different users and project teams by creating isolated virtual machine environments for each using the same physical hardware. This optimized utilization of the costly mainframes via time-sharing of resources.
- What role did virtual machines play in the history of computing?
Virtual machines played a pivotal role in computing history by providing the partitioning and abstraction capabilities that enabled time-sharing and multiprogramming capabilities on early mainframe systems. This ultimately paved the way for modern virtualization and cloud computing.
- How have virtual machines evolved since the 1960s?
From solely mainframes, VMs advanced to widespread enterprise server usage in the 1990s and 2000s. Performance improved drastically after hardware acceleration support in the mid-2000s. VMs are now ubiquitous across personal devices, enterprise infrastructure, and public cloud platforms thanks to expanded capabilities.
- What makes virtual machines different from containers?
Containers provide operating system level virtualization by abstracting the OS kernel, whereas VMs virtualize hardware resources to emulate an entire computer system and provide an isolated environment to install guest operating systems.
- Do virtual machines require special hardware or CPU features?
Originally software-only, hardware acceleration from CPU extensions like Intel VT-x and AMD-V have now become standard to significantly improve VM performance. Hypervisors can still leverage software-only virtualization as a fallback if needed.
- What are examples of modern virtual machine software?
VMware, Hyper-V, VirtualBox, QEMU, and KVM are all commonly used hypervisor and virtual machine monitor software, while platforms like VMware vSphere ESXi and Microsoft Hyper-V Server provide enterprise VM management capabilities.
- What’s the difference between a hypervisor and virtual machine monitor?
The terms are synonymous – both refer to the software that manages virtual machines, handles resource allocation between VMs, runs and monitors guest VMs, and abstracts the underlying host hardware.
- Do cloud platforms use virtual machine technology?
Absolutely, virtual machines are a fundamental building block of major cloud platforms like AWS EC2, Azure Virtual Machines, and GCP Compute Engine which leverage VMs to provide scalable, on-demand computing resources that can be quickly provisioned and deprovisioned.
- How has virtualization simplified IT and business operations?
By encapsulating workloads in portable virtual machines, virtualization and VMs have simplified migration, disaster recovery, scaling, maintenance, deployment, testing, and security while increasing infrastructure flexibility leading to IT efficiency gains.
- Are mainframes still used alongside modern virtual machine implementations?
Yes, mainframes continue to run high-volume transactional workloads across industries thanks to ongoing virtualization innovation that has helped System Z environments evolve to provide both scale up and scale out capabilities despite much lower unit volumes than x86 servers.