Article ID : S500010573 / Last Modified : 11/04/2018Print

What is the page faults on the memory manager of the system monitor of Windows9*?

    What is the page faults on the memory manager of the system monitor of Windows9*?

    - "page faults" occurs on "Memory Manager" of "System Monitor".
    Does it mean something wrong with my operation/computer?

    - What does the "page faults" on "Memory Manager" mean?

    To check the page faults on the memory manager.

    (Procedure)

    1. Click the "Start" button and then click "System Monitor" from "Programs"-"Accessories"-"System Tools".

    2. When "System Monitor" starts, click "Add Item" from "Edit".

    3. Select "Memory Manager" from "Category" and "page faults" from "item" on the "Add Item" window and click the "OK" button.

    It does not mean anything wrong with your operation/computer.
    It shows the number of page faults per second.

    "page faults" on the memory manager does not mean "Error" of the system. It indicates the number of page faults per second.
    Windows handles larger space than the actually installed memory, storing memory that cannot be stored in the actual memory to the hard disk drive as virtual memory. When an application accesses the memory that does not exist in the actual memory or the virtual memory, the page faults occur.

    Tasks and data that have not been used for a certain period of time are moved to the virtual memory. Once they are moved to the virtual memory, the meaning of their memory addresses changes from the meaning before the move. When other applications or operation systems access them at their previous addresses, therefore, they end up accessing non-existing memory or unintended addresses. Such accesses are counted as "page faults".

    Actually, this "page faults" triggers the system to map the image at the time when Windows accessed the actual memory. In other words, the occurrence of "page faults" on "Memory Manager" does not mean an error or a malfunction of the system but simply represents the monitoring of the operation of the system.

    (Remarks)
    To save a memory image on the actual memory to the virtual memory on a hard disk drive is called "page-out", and to move a virtual memory image on the hard disk drive to the actual memory is called "page-in". "page-out" and "page-in", which you can check with the system monitor, indicate "the number of pages swapped from the memory to the hard disk drive and written to that hard disk drive in one second" and "the number of pages swapped from the hard disk drive to the memory in one second" respectively. Displaying "page-out" and "page-in" side by side on the screen would clearly show their relationship.

    For example, as BatteryScope checks the battery capacity at regular intervals, "page-out" and "page-in" take place with the timing of its checking, which is normal operation. Some models operate differently as stay-resident applications affect "page-out" and "page-in".