A computer term for a performance enhancing feature of some software. Virtual memory is a process where hard disk storage space is borrowed and caused to act as if it were additional RAM. The system will then be able to perform more complex functions just as if it had the additional RAM memory actually installed. See also RAM.

Technique for using disk storage space to emulate random access memory.

A process of creating "extra" RAM by using the hard drive as a temporary RAM. A segment of the hard drive is allocated to virtual memory; if an application requires more memory than is available, the active components of the application are loaded into the RAM while the other inactive parts are load into the virtual memory. The downside to this is that virtual memory is much slower than RAM so the application runs slower if components in virtual memory are used.

Addressable memory beyond the limits of available physical memory. An operating system extends physical memory by storing on a secondary storage device, such as a hard disk, code and data not immediately required by the CPU.

a technique which gives the computer seemingly limitless memory for processing. In reality, data is written back to the computer disk temporarily until it is needed again for processing in RAM.

The process of increasing the apparent size of a computer's random-access memory (RAM) by using a section of the hard disk storage as an extension of RAM.

Address space is divided up into chunks called pages. A page needs to be in physical memory when accessed by the CPU, but may be stored on disk if not needed for a while, thus freeing physical memory for other processes that need it.

the appearance of having somewhat unlimited memory through a capability that allows only those programs that are needed to be held in memory at a given time and then exchanged with other programs when appropriate.

An area of imaginary memory that some operating systems support. Virtual memory expands the available RAM by commandeering hard-disk space and making it work as pseudo RAM. The more RAM you have, the more applications you can open at the same time. True RAM works many times faster than virtual memory. Once your computer starts using hard-drive space for RAM, it slows down considerably.

A means of increasing the size of a computer's random-access memory (RAM) by using part of the hard disk as an extension of RAM.

a system to handle the memory hierarchy, providing an automatic method of transferring the contents of blocks of memory (pages) into the main memory when needed. Relies on using two addresses for each stored word, a virtual address which is generated by the processor and the corresponding real address for accessing the memory. [SILC99

In computer systems, the memory as it appears to, i.e., as it is available to, the operating programs running in the central processing unit (CPU).

Virtual memory is hard disk space that the computer uses as if it were RAM. Disk space used for virtual memory is not available for storing files. Data stored in virtual memory is lost on shut down as with physical RAM.

A use of disk drive storage that simulates RAM. Some operating systems (not DOS) borrow parts of the disk drive and swap out massive chunks of memory to a file on disk -- a swap file. That way true memory (RAM) is made available for programs that need it. The memory saved on disk can be put back into real memory when it's needed later.

The total amount of memory used (including both memory in RAM and swapped out memory to disk).

Memory is hardware that your computer uses to load the operating system and run ...

A trick used by a computer's operating system to pretend that it has access to more memory than is actually available. For example, a program running on the computer may require ten mega-bytes to store its data, but the computer may have only five mega-bytes of memory available. To get around this problem, whenever the program attempts to access a memory location that does not physically exist, the operating system performs a slight-of-hand and exchanges some of the contents in the memory with data on the hard disk.

The sum of the system's physical memory and swap space.

(computer science) memory created by using the hard disk to simulate additional random-access memory; the addressable storage space available to the user of a computer system in which virtual addresses are mapped into real addresses

Hard disk space used as an extension of RAM. This usually causes the PC to be slow.

A technique by which operating systems load more programs and data into memory than they can hold. Parts of the programs and data are kept on disk and constantly swapped back and forth into system memory. The applications' software programs are unaware of this setup and act as though a large amount of memory is available.

Part of the space on your hard disk - this reserved space is called the swap disk - can be configured to act as if it were RAM memory whenever more system memory is called for.

A memory-management technique that uses hard drive space as an extension to a PC's RAM.

The set of storage locations in physical memory and on disk, together, that is referred to by virtual addresses. The amount of memory available by the system is always perceived by the system to be the maximum virtual memory possible. The real limitation to virtual memory is the total quantity of physical memory (RAM) and disk space available. An inbalance between RAM and virtual memory required can severly slow down processing or even bring it to a screaming halt.

A section of a hard drive used to augment a computer's RAM, or main memory. Different operating systems have different ways of dealing with virtual memory. UNIX and Linux often use a separate hard drive partition dedicated to virtual memory, while Windows uses a file or files on any number of hard drive partitions. However, Linux and UNIX can be configured to use a swap file as needed also. Virtual memory is used when the operating system runs low on physical memory. Virtual memory is also used to swap out lesser used portions of physical memory, freeing it up for other operations.

Because your computer has a finite amount of RAM, it is possible to run out of memory when too many programs are running at one time. Virtual memory increases available memory by enlarging the "address space," or places in memory where data can be stored. It does this by using hard disk space for additional memory allocation. However, since the hard drive is much slower than RAM, data stored in virtual memory must be mapped back to real memory in order to be used.

This is a section of a hard drive used to augment a computer's RAM. Different operating systems have different ways of dealing with virtual memory. UNIX and Linux use a separate hard drive partition dedicated to virtual memory, while Windows can use part of any hard drive partition. Virtual memory is used when the operating system runs low on physical memory or RAM. Virtual memory is also used to swap out lesser used portions of physical memory, freeing it up for other operations.

Memory which resides on the slow, hard disk and not in the fast electronics.

Apparently extended memory on a computer, consisting partly of real memory (RAM) and partly of disk space. A technique to handle programs and applications that are too large to fit into real memory. Can degrade performance if used too heavily.

This is a scheme by which disk space is made to substitute for the more expensive RAM space. Using it will often enable a comptuer to do things it could not do without it, but it will also often result in an overall slowing down of the system. The concept of swap space is very similar.

Sometimes called (by Adobe in Photoshop) a scratch disk. When not enough "real" memory (RAM) is available, this process borrows a chunk of your hard disk to store data and perform imaging calculations.

Virtual memory will temporarily assemble extra RAM by use of permanent media.

Aka page file. A portion of storage memory utilized for processing memory or caching. It provides alternate memory addresses in groups called pages. These pages are converted to real memory address when the program is actually executed. This paging or swapping is much slower than using real processing memory. However it is great for freeing up real RAM.

The space on the hard disk that Windows 2000 uses as memory. Because of virtual memory, the amount of memory taken from the perspective of a process can be much greater than the actual physical memory in the computer. The operating system does this in a way that is transparent to the application, by paging data that does not fit in physical memory to and from the disk at any given instant.

A method of expanding the amount of available memory by combining physical memory (RAM) with cheaper and slower storage such as a swap area on a hard disk.

Memory beyond what is actually available, but which programs believe is actually available memory in the system. See swap.

Memory space allocated on a disk, rather than in RAM. Virtual memory allows large data structures that would not fit in conventional memory, at the expense of slow access.

Virtual memory is an operating system feature which uses secondary storage (the hard disk drive) to free up primary storage (RAM) in order to enable application programs to access more RAM than which is physically available.

Space on a hard disk that Windows NT uses as if it were actually memory. Windows NT does this through the use of paging files. The benefit of using virtual memory is that you can run more applications at one time than your system?s physical memory would otherwise allow. The drawbacks are the disk space required for the virtual-memory paging file and the decreased execution speed when swapping is required.

Simulated memory. When RAM is full, the computer swaps data to the hard disk and back as needed.

Virtual (or logical) memory is a concept that, when implemented by a computer and its operating system, allows programmers to use a very large range of memory or storage addresses for stored data. The computing system maps the programmer's virtual addresses to real hardware storage addresses. Usually, the programmer is freed from having to be concerned about the availability of data storage.

Memory allocation service supporting multiple, protected address spaces. On systems with secondary storage, applications can use much more virtual memory than the memory physically available. This module is specifically designed to implement distributed UNIX subsystems on top of the microkernel.

Area of a computers hard disk used when more memory is required than is installed in the computer. When the computer runs out of memory, it starts 'paging' data to Virtual Memory.

Memory that appears to an application to be larger and more uniform than it is.

Addressable space that appears to be real storage. From virtual storage, instructions and data are mapped into real storage locations. The size of virtual storage is limited by the addressing scheme of the computer system and by the amount of auxiliary storage available, not by the actual number of system memory locations. Contrast with real memory. Synonymous with virtual storage.

The use of the hard drive as potential RAM

Computer memory, separate from the main memory of a specific machine, that can be used as an extension of the machine's main memory.

The part of a hard disc used to store data on a temporary basis and swap it in and out of RAM as required.

Configuration in which portions of the address space are kept on a secondary medium, such as a disk or auxiliary memory. When a reference is made to a location not resident in main memory, the virtual memory manager loads the location from secondary storage before the access completes. If no space is available in main memory, data is written to secondary storage to make some available. Virtual memory is used by almost all uniprocessors and multiprocessors to increase apparent memory size, but is not available on some array processors and multicomputers.

Temporary storage that is used by a computer to run programs that need more memory than the computer has. For example, programs could have access to 4 GB of virtual memory on a computer's hard drive, even if the computer has only 32 MB of RAM.

every process in the system gets its own memory address space, independent of the other processes.

(n.) A system that stores portions of an address space that are not being actively used in in some medium other than main high-speed memory, such as a disk or slower auxiliary memory medium. When a reference is made to a value not presently in main memory, the virtual memory manager must swap some values in main memory for the values required. Virtual memory is used by almost all uniprocessors and multiprocessors, but is not available on some array processors and multicomputers, which still employ real memory storage only on each node.

Memory contents that appear to be in contiguous addresses, but are actually mapped to different physical memory locations by hardware action of the translation lookaside buffer (TLB) and page tables managed by the IRIX kernel. The kernel can exploit virtual memory to give each process its own address space, and to load many more processes than physical memory can support.

Memory addresses and data that appear to the CPU to be in RAM but actually are on a hard disk. Special software manages this memory and gives the CPU access to it.

Disk storage that is treated as RAM (memory). Both Windows 3.1 and Windows 95 can use disk space as virtual memory.

A method for increasing addressable RAM by using the hard drive. For example, in a system with 16 MB of RAM and 16 MB of virtual memory set up on the hard drive, the operating system would manage the system as though it had 32 MB of physical RAM.

A way to provide large memory spaces to processes. Virtual memory usually exceeds the actual memory capacity. Virtual memory is broken into pages for ease of management. Active pages are in memory, while the rest are on a disk.

Disk space on a hard drive that is identified asRAMthough the operating system, or other software. Since hard drive memory is often less expensive than additional RAM, it is an inexpensive way to get more memory and increase the operating speed of a application.

A subsystem that uses a portion of physical memory, disk swap space, and daemons and algorithms in order to control the allocation of memory to processes and to the UBC.

The use of secondary storage devices and primary storage to expand effectively a computer system's primary storage.

Is hard disk space your computer uses as if it were RAM. This disk space is not available for storing files. While virtual memory improves the performance of programs designed for a PowerPC-based computer, using it can make your computer run more slowly.

the use of disk space to simulate additional RAM, also called a swap file. Virtual memory allows you to run programs for which you would otherwise not have sufficient RAM. Because disk access is much slower than RAM access, virtual memory will have poor performance relative to that of actual RAM. Refer to the TechNote, " Memory Configurations." for instructions on configuring virtual memory.

This is system memory that is simulated by the hard drive. When all the RAM is being used (for example if there are many programs open at the same time) the computer will swap data to the hard drive and back to give the impression that there is slightly more memory.

hard disk storage space used as RAM by the System software (built in to System 7 and above); set via the Memory Control Panel ( note: many newer applications run much more stable with Virtual Memory turned off)

The amount of RAM each application 'perceives'. (This is 4Gig split in half, 2Gig for the app, 2Gig for the system areas) See Physical Memory.

A technique that enables a certain portion of hard disk space to be used as auxiliary memory so that your computer can access larger amounts of data than its main memory can hold at one time.

Virtual Storage Access Method

A way of using disk storage space to make the computer work as if it had more memory. When a file or program is too big for the computer to work with in its memory, part of the data is stored on disk. This virtual storage is divided into segments called pages; each page is correlated with a location in physical memory, or RAM. When an address is referenced, the page is swapped into memory; it is sent back to disk when other pages must be called.The program runs as if all the data is in memory. Win 9x uses a Swap file and WinNT/2000 uses a paging file(s). Since disks are slower, this is much slower than memory itself.

The use of hard disk storage to expand effective memory capability

The use of a portion of the hard disk to swap out data when insufficient RAM exists to hold all such data.

Operating system allocates a portion of a storage medium, usually the hard disk, to function as additional RAM. 8.10

Temporary storage used by a computer to run programs that need more memory than it has. For example, programs could have access to 4 gigabytes of virtual memory on a computer's hard drive, even if the computer has only 32 megabytes of RAM. The program data that does not currently fit in the computer's memory is saved into paging files. See also: virtual printer memory; paging file; Virtual Memory Size

The memory that the operating system allocates to programs and data. Virtual memory is mapped to RAM (physical memory). When there is not enough RAM to run all programs, some memory pages can be temporarily paged or swapped from RAM to disk.

using part of your hard drive as though it were "RAM".

(n.) A condition in which a user program can be larger than physical memory. Virtual memory is possible through a storage hierarchy in which a program's virtual image is stored in secondary storage while main memory stores only active program segments.

Virtual memory is an addressing scheme implemented in hardware and software that allows non-contiguous memory to be addressed as if it is contiguous.