memory allocation

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Related to memory allocation: Memory management, Dynamic memory allocation

memory allocation

Reserving memory for specific purposes. At startup, operating systems and applications reserve fixed amounts of memory (RAM) and may allocate more as needed. Although a virtual memory function simulates an almost unlimited amount of memory, there is always a certain amount of "real" memory needed to run the program. See virtual memory.

Allocate and Release
Depending on the language, programmers have to specifically release memory that is no longer used. This is tedious and error prone because it is easy to forget to deallocate, causing unused memory to remain until the program is closed. For example, Java and the .NET environment perform "garbage collection" and release memory automatically. C and C++ do not.

Disk Caches
Memory is also allocated for a disk cache by the operating system and may be configurable by the user. A disk cache retains large chunks of data from storage in faster RAM. However, a large disk cache that speeds up one application may slow down another because there is less RAM available. See cache.

Awful in the Days of DOS
On PCs before DOS 6, memory management was a mess. Users were expected to allocate the right mix of expanded memory (EMS) and extended memory, causing third-party memory managers such as QEMM and 386MAX to become popular because they did it automatically. See PC memory management.
References in periodicals archive ?
13, the average data transfer time of the OpenCL implementations was much longer than the memory allocation time of the C and the OpenMP designs.
Enum will double memory allocation than ordinary static constant, so do not use it.
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4 also includes a preview implementation of the malloc memory allocation library optimized for multicore processors.
An example we encountered involved a client trying to locate the cause of a memory crash, where our audit found that the root cause was inconsistent memory allocation methods being used on the same global object accessed by different system modules.
Improved performance of files across the network with highly efficient memory allocation algorithms that improve the flow of files across the network.
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