virtual memory – Windows Blog by Brink

virtual memory

Enable or Disable Clear Virtual Memory Paging File at Shutdown in Windows 11

A paging file (aka: “page file” and “virtual memory”) enables the system to remove infrequently accessed modified data from physical memory to let the system use physical memory more efficiently for more frequently accessed data. Windows also uses the page file to store data when physical memory (RAM) is full.

The Shutdown: Clear virtual memory pagefile policy setting determines whether the virtual memory paging file is cleared when the device is shut down or restarted. Virtual memory support uses a system paging file to swap pages of memory to disk when they aren’t used. On a running device, this paging file is opened exclusively by the operating system, and it’s well protected. However, devices that are configured to allow other operating systems to start should verify that the system paging file is cleared as the device shuts down. This confirmation ensures that sensitive information from process memory that might be placed in the paging file isn’t available to an unauthorized user who manages to directly access the paging file after shutdown.

Important information that is kept in real memory might be written periodically to the paging file. This periodical write-operation helps devices handle multitasking functions. A malicious user who has physical access to a server that has been shut down can view the contents of the paging file. The attacker can move the system volume into a different computer and then analyze the contents of the paging file. This process is a time-consuming one, but it can expose data that is cached from RAM to the paging file. A malicious user who has physical access to the server can bypass this countermeasure by unplugging the server from its power source.

Enabling the Shutdown: Clear virtual memory pagefile policy causes the amount of time that is required to complete a shut down or restart depends on the size of the page file. It takes longer to shut down and restart the device, especially on devices with large paging files. Because the process overwrites the storage area that is used by the page file several times, it could be several minutes before the device completely shuts down or restarts.

This tutorial will show you how to enable or disable clear virtual memory paging file at shutdown or restart for all users in Windows 10 and Windows 11.

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Enable or Disable Virtual Memory Paging File Encryption in Windows 11

A paging file (aka: “page file” and “virtual memory”) enables the system to remove infrequently accessed modified data from physical memory to let the system use physical memory more efficiently for more frequently accessed data. Windows also uses the page file to store data when physical memory (RAM) is full.

Encrypting the page file prevents malicious users from reading data that has been paged to disk, but also adds processing overhead for filesystem operations.

This tutorial will show you how to enable or disable virtual memory paging file encryption in Windows 10 and Windows 11.

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Manage Virtual Memory Paging File in Windows 11

A paging file (aka: “page file” and “virtual memory”) enables the system to remove infrequently accessed modified data from physical memory to let the system use physical memory more efficiently for more frequently accessed data.

Windows also uses the page file to store data when physical memory (RAM) is full.

The system automatically manages the size of the paging file (“C:\pagefile.sys”) on the Windows drive by default.

However, there may be times you may need to manually manage the paging file. For example:

  • If the C: drive that Windows is installed on is small in size, you may wish to remove the paging file from that drive, and add a paging file to another drive with more space instead.
  • If you use a lot of memory, then you may wish to add a paging file to another drive to have available if needed.
  • If you don’t use a lot of memory and your paging file is large in size, you may wish to use a smaller custom size.
  • If you are getting a BSOD PAGE_FAULT_IN_NONPAGED_AREA or KERNEL_DATA_INPAGE_ERROR or Low Memory type error when the paging file size is not system managed, you may need to set a larger custom size for the paging file.

This tutorial will show you how to manage the virtual memory paging file for each drive on your Windows 10 and Windows 11 PC.

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How to Allow or Prevent Users and Groups to Create a Pagefile in Windows 10

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.

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