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Memory-mapped File
A memory-mapped file is a segment of virtual memory that has been assigned a direct byte-for-byte correlation with some portion of a file or file-like resource. This resource is typically a file that is physically present on disk, but can also be a device, shared memory object, or other resource that the operating system can reference through a file descriptor. Once present, this correlation between the file and the memory space permits applications to treat the mapped portion as if it were primary memory. History TOPS-20 PMAP An early () implementation of this was the PMAP system call on the DECSYSTEM-20, DEC-20's TOPS-20 operating system, a feature used by Software House's System 1022 (database), System-1022 database system. SunOS 4 mmap SunOS 4 introduced Unix's mmap, which permitted programs "to map files into memory." Windows Growable Memory-Mapped Files (GMMF) Two decades after the release of TOPS-20's PMAP, Windows NT was given Growable Memory-Mapped Files (GMMF). Sinc ...
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Virtual Memory
In computing, virtual memory, or virtual storage is a Memory management (operating systems), memory management technique that provides an "idealized abstraction of the storage resources that are actually available on a given machine" which "creates the illusion to users of a very large (main) memory". The computer's operating system, using a combination of hardware and software, maps memory addresses used by a program, called ''Virtual address space, virtual addresses'', into ''physical addresses'' in computer memory. Main storage#Primary storage, Main storage, as seen by a process or task, appears as a contiguous address space or collection of contiguous Memory segmentation, segments. The operating system manages virtual address spaces and the assignment of real memory to virtual memory. Address translation hardware in the CPU, often referred to as a memory management unit (MMU), automatically translates virtual addresses to physical addresses. Software within the operating sys ...
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Memory Page
A page, memory page, or virtual page is a fixed-length contiguous block of virtual memory In computing, virtual memory, or virtual storage is a Memory management (operating systems), memory management technique that provides an "idealized abstraction of the storage resources that are actually available on a given machine" which "cre ..., described by a single entry in the page table A page table is the data structure Image:Hash table 3 1 1 0 1 0 0 SP.svg, 315px, A data structure known as a hash table. In computer science, a data structure is a data organization, management, and storage format that enables efficient access .... It is the smallest unit of data for memory management in a virtual memory operating system An operating system (OS) is system software System software is software designed to provide a platform for other software. Examples of system software include operating systems (OS) like macOS, Linux, Android (operating system), Android and Mi .... Si ...
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Process (computing)
In computing Computing is any goal-oriented activity requiring, benefiting from, or creating computing machinery. It includes the study and experimentation of algorithmic processes and development of both computer hardware , hardware and software. It has sci ..., a process is the instance of a computer program In imperative programming, a computer program is a sequence of instructions in a programming language that a computer can execute or interpret. In declarative programming, a ''computer program'' is a Set (mathematics), set of instructions. A comp ... that is being executed by one or many threads. It contains the program code and its activity. Depending on the operating system An operating system (OS) is system software System software is software designed to provide a platform for other software. Examples of system software include operating systems (OS) like macOS, Linux, Android (operating system), Android and Mi ... (OS), a process may be made up of multiple ...
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Unix-like
A Unix-like (sometimes referred to as UN*X or *nix) operating system An operating system (OS) is system software System software is software designed to provide a platform for other software. Examples of system software include operating systems (OS) like macOS, Linux, Android (operating system), Android and Mi ... is one that behaves in a manner similar to a Unix Unix (; trademarked as UNIX) is a family of multitasking, multiuser Multi-user software is computer software Software is a collection of Instruction (computer science), instructions that tell a computer how to work. This is in contrast t ... system, while not necessarily conforming to or being certified to any version of the Single UNIX Specification The Single UNIX Specification (SUS) is the collective name of a family of standards for computer A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations automatically. Modern computers can .... A ...
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Microsoft Windows
Microsoft Windows, commonly referred to as Windows, is a group of several proprietary {{Short pages monitor

Loader (computing)
In computer systems A computer is a machine A machine is a man-made device that uses power to apply forces and control movement to perform an action. Machines can be driven by animals and people A people is a plurality of person A person (plural ... a loader is the part of an operating system An operating system (OS) is system software System software is software designed to provide a platform for other software. Examples of system software include operating systems (OS) like macOS, Linux, Android (operating system), Android and Mi ... that is responsible for loading programs and libraries A library is a collection of materials, books or media that are easily accessible for use and not just for display purposes. It is responsible for housing updated information in order to meet the user's needs on a daily basis. A library provi .... It is one of the essential stages in the process of starting a program, as it places programs into memory and pre ...
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Memory Management Unit
A memory management unit (MMU), sometimes called paged memory management unit (PMMU), is a computer hardware Computer hardware includes the physical parts of a computer, such as the computer case, case, central processing unit (CPU), Computer monitor, monitor, Computer mouse, mouse, Computer keyboard, keyboard, computer data storage, graphics card, so ... unit having all memory Memory is the faculty of the by which or is , stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If s could not be remembered, it would be impossible for language, r ... references passed through itself, primarily performing the translation of virtual memory addresses to physical address 300px, Diagram of relationship between the virtual and physical address spaces In computing Computing is any goal-oriented activity requiring, benefiting from, or creating computing machinery. It includes the study and experimentatio ...
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NVM Express
NVM Express (NVMe) or Non-Volatile Memory Host Controller Interface Specification (NVMHCIS) is an open, logical-device interface functional specification, specification for accessing a computer's non-volatile storage media usually attached via PCI Express (PCIe) bus. The acronym ''NVM'' stands for ''non-volatile memory'', which is often NAND flash memory that comes in several physical form factors, including solid-state drives (SSDs), PCI Express (PCIe) add-in cards, and M.2 cards, the successor to mSATA cards. NVM Express, as a logical-device interface, has been designed to capitalize on the low Hard disk drive performance characteristics#Access time, latency and internal parallelism of solid-state storage devices. Architecturally, the logic for NVMe is physically stored within and executed by the NVMe controller chip that is physically co-located with the storage media, usually an SSD. Version changes for NVMe, e.g., 1.3 to 1.4, are incorporated within the storage media, and do ...
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64-bit
In computer architecture, 64-bit Integer (computer science), integers, Memory address, memory addresses, or other Data#Uses%20of%20data%20in%20computing, data units are those that are 64 bits (8 Octet (computing), octets) wide. Also, 64-bit central processing unit (CPU) and arithmetic logic unit (ALU) architectures are those that are based on processor registers, address buses, or Bus (computing), data buses of that size. 64-bit microcomputers are computers in which 64-bit microprocessors are the norm. From the software perspective, 64-bit computing means the use of machine code with 64-bit virtual memory addresses. However, not all 64-bit instruction sets support full 64-bit virtual memory addresses; x86-64 and ARMv8, for example, support only 48 bits of virtual address, with the remaining 16 bits of the virtual address required to be all 0's or all 1's, and several 64-bit instruction sets support fewer than 64 bits of physical memory address. The term ''64-bit'' describes a gen ...
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IA-32
IA-32 (short for "Intel Architecture, 32-bit", sometimes also called i386) is the 32-bit 32-bit microcomputer A microcomputer is a small, relatively inexpensive computer with a microprocessor as its central processing unit (CPU). It includes a microprocessor, Computer memory, memory and minimal input/output (I/O) circuitry mount ... version of the x86 x86 is a family of instruction set architecture In computer science, an instruction set architecture (ISA), also called computer architecture, is an abstract model of a computer. A device that executes instructions described by that ISA, ... instruction set architecture In computer science Computer science deals with the theoretical foundations of information, algorithms and the architectures of its computation as well as practical techniques for their application. Computer science is the study of , ..., designed by Intel Intel Corporation is an American multinational corporation A multinat ...
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32-bit
32-bit microcomputer A microcomputer is a small, relatively inexpensive computer with a microprocessor as its central processing unit (CPU). It includes a microprocessor, Computer memory, memory and minimal input/output (I/O) circuitry mounted on a single printed ci ...s are computers in which 32-bit microprocessor A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit An integrated circuit or monolithic integrated circuit (also referred to as an IC, a chip, or a microchip ...s are the norm. Range for storing integers A 32-bit register can store 232 different values. The range Range may refer to: Geography * Range (geographic)A range, in geography, is a chain of hill A hill is a landform A landform is a natural or artificial feature of the solid surface of the Earth or other planetary body. Landforms together ... of integer An integer (from the Latin Latin (, or , ...
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Memory Address
In computing Computing is any goal-oriented activity requiring, benefiting from, or creating computing machinery. It includes the study and experimentation of algorithmic processes and development of both computer hardware , hardware and software. It has sci ..., a memory address is a reference to a specific memory Memory is the faculty of the by which or is , stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If s could not be remembered, it would be impossible for language, r ... location used at various levels by software Software is a collection of instructions that tell a computer A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations automatically. Modern computers can perform generic sets of operatio ... and hardware Hardware may refer to: Technology Computing and electronics * Computer hardware, physical parts of a computer ...
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