A supervisory program or supervisor is a
computer program
A computer program is a sequence or set of instructions in a programming language for a computer to execute. Computer programs are one component of software, which also includes documentation and other intangible components.
A computer program ...
, usually part of an
operating system
An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs.
Time-sharing operating systems schedule tasks for efficient use of the system and may also in ...
, that controls the execution of other
routines and regulates
work scheduling,
input/output
In computing, input/output (I/O, or informally io or IO) is the communication between an information processing system, such as a computer, and the outside world, possibly a human or another information processing system. Inputs are the signals ...
operations,
error actions, and similar functions and regulates the flow of work in a
data processing
Data processing is the collection and manipulation of digital data to produce meaningful information.
Data processing is a form of ''information processing'', which is the modification (processing) of information in any manner detectable by an ...
system.
It can also refer to a program that allocates computer component space and schedules computer events by
task queuing and system
interrupt
In digital computers, an interrupt (sometimes referred to as a trap) is a request for the processor to ''interrupt'' currently executing code (when permitted), so that the event can be processed in a timely manner. If the request is accepted, ...
s. Control of the system is returned to the supervisory program frequently enough to ensure that demands on the system are met.
Historically, this term was essentially associated with
IBM's line of
mainframe
A mainframe computer, informally called a mainframe or big iron, is a computer used primarily by large organizations for critical applications like bulk data processing for tasks such as censuses, industry and consumer statistics, enterprise ...
operating systems starting with
OS/360
OS/360, officially known as IBM System/360 Operating System, is a discontinued batch processing operating system developed by IBM for their then-new System/360 mainframe computer, announced in 1964; it was influenced by the earlier IBSYS/IBJOB ...
. In other operating systems, the supervisor is generally called the
kernel
Kernel may refer to:
Computing
* Kernel (operating system), the central component of most operating systems
* Kernel (image processing), a matrix used for image convolution
* Compute kernel, in GPGPU programming
* Kernel method, in machine learnin ...
.
In the 1970s, IBM further abstracted the supervisor
state
State may refer to:
Arts, entertainment, and media Literature
* ''State Magazine'', a monthly magazine published by the U.S. Department of State
* ''The State'' (newspaper), a daily newspaper in Columbia, South Carolina, United States
* ''Our S ...
from the hardware, resulting in a
hypervisor
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 calle ...
that enabled
full virtualization
In computer science, virtualization is a modern technique developed in late 1990s and is different from simulation and emulation. Virtualization employs techniques used to create instances of an environment, as opposed to simulation, which model ...
, i.e. the capacity to run multiple operating systems on the same machine totally independently from each other. Hence the first such system was called ''Virtual Machine'' or ''
VM''.
References
*
Operating system technology
{{computing-stub