Virtual Memory
An OS technique using disk space to simulate additional RAM, allowing programs to use more memory than physically available.
Also: swap space · page file
Definition
Virtual memory is a memory management technique that creates an illusion of a large, contiguous memory space by using both physical RAM and disk storage (swap space or page file). The OS maps virtual addresses to physical addresses using page tables, and when physical RAM is full, it moves infrequently used pages to disk (paging/swapping). Virtual memory isolates processes from each other and allows programs to use more memory than physically installed. However, heavy swapping causes severe performance degradation.
Example
“A computer with 8 GB of RAM runs a video editing program requiring 12 GB by using 4 GB of virtual memory on the hard drive as overflow storage.”
Synonyms
- swap space
- paged memory
- extended memory
Antonyms / Opposites
- physical memory
- RAM-only execution
Images
CC-licensed · free to useVideo
Related Terms
- memory-management
- paging
- swap
- process