Paging is a memory management scheme by which a PC stores and retrieves data from secondary storage for use in main memory. In this scheme, the operating system retrieves data from secondary storage in same-size blocks called pages. Paging is an important part of virtual memory implementations in modern operating systems, using secondary storage to let programs exceed the size of available physical memory.
For simplicity, main memory is called “RAM” (abbreviated from “random-access memory”) and secondary storage is called “disk” (a shorthand for “hard disk drive”), but the concepts do not depend on whether these terms apply literally to a specific computer system.
Virtual memory is a memory management technique that is implemented using both hardware and software. It maps memory addresses used by a program, called virtual addresses, into physical addresses in computer memory. Main storage as seen by a process or task appears as a contiguous address space or collection of contiguous segments. Windows 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 or MMU, automatically translates virtual addresses to physical addresses. Software within Windows may extend these capabilities to provide a virtual address space that can exceed the capacity of real memory and thus reference more memory than is physically present in the computer.
The primary benefits of virtual memory include freeing applications from having to manage a shared memory space, increased security due to memory isolation, and being able to conceptually use more memory than might be physically available, using the technique of paging.
Basically, a paging file is an area on the hard disk that Windows uses as if it were RAM when you run out of available RAM.
By default, only Administrators are allowed to create a pagefile.
This tutorial will show you how to allow or prevent specific users and groups to create a pagefile in Windows 10.
Virtual memory support uses a system pagefile to swap pages of memory to disk when they are not used. On a running system, this pagefile is opened exclusively by the operating system, and it is well protected. However, systems that are configured to allow booting to other operating systems might have to make sure that the system pagefile is wiped clean when this system shuts down. This ensures that sensitive information from process memory that might go into the pagefile is not available to an unauthorized user who manages to directly access the pagefile.
Some third-party programs can temporarily store unencrypted (plain-text) passwords or other sensitive information in memory. Because of the Windows virtual memory architecture, this information can be present in the paging file.
Although clearing the paging file is not a suitable substitute for physical security of a computer, you might want to do this to increase the security of data on a computer while Windows is not running.
This tutorial will show you how to turn on or off to clear the virtual memory pagefile when you shut down or restart Windows 10.