Share via


What is Virtual Memory?

Over the holiday break I was reading through reader feedback and found a great question: What is "Virtual Memory?" I know there's a great joke in that question somewhere but I can’t remember what it is...

Anyway, when you're talking about your computer, virtual memory refers to a technique the operating system uses to help it work with your applications and files. The Microsoft Computer Dictionary definition is: "Memory that appears to an application to be larger and more uniform than it is. Virtual memory can be partially simulated by secondary storage such as a hard disk."

OK, so what does that mean? To understand virtual memory, you first need to understand the hardware your computer uses to store information.

First, there's the hard drive, where your software and data files are stored permanently. Your hard drive looks a bit like this:

Image of hard drive
Hard drive

Second, there are memory chips, which are used to temporarily store the software and information (such as documents and pictures) your computer is actively working with. Memory chips look like this:

Image of memory chip
Memory chip

You also store information on removable media, such as CDs and USB drives, but this discussion is confined to the storage that stays in your computer.

You'll often hear the memory chips in your computer referred to as RAM, which is short for Random Access Memory (which means pretty much just that, memory that's used in a random, rather than sequential, manner). The more RAM your computer has, the more software and files it can juggle at the same time without having to read or write stuff onto or off of your hard drive. This is why computers with more RAM tend to run faster than those with less.

Regardless of how many RAM chips you've got in your computer, virtual memory helps increase your computer's performance by using hard drive space as a way to extend the storage area available to RAM. Also called disk memory, this process uses something called a page file to move information in and out of the RAM chips on your computer.

Image demonstrating how virtual memory works
Virtual memory uses page files to move information between your hard drive and RAM

Generally, you shouldn't run into trouble with the virtual memory functionality on your computer. If you get an error message referring to virtual memory, you can search for potential causes on https://support.microsoft.com, or contact your technical support resource.

I'll close with a trivia note: In researching this topic, I saw virtual memory referred to as one of the under-acknowledged computing breakthroughs of the 20th century. It was first used in mainframe computers in the 1960s.

—Robbin Young

Comments

  • Anonymous
    February 16, 2006
    What is the appropriate setting for the Virtual Memory ? I have Windows Xp home and run a Gateway 3.1 meg 64 byte system with a 250 gig h.d. Thanks

    Martin

  • Anonymous
    February 22, 2006
    The comment has been removed

  • Anonymous
    February 22, 2006
    The virtual memory shoud be 2 times of your physical memory.ie if you have 512MB RAM inyour system then the virtual memory should be 1GB.
    bye

  • Anonymous
    February 22, 2006
    I have received a message from Dell Support to "increase size of Virtual Memory File." The exact words are: The current virtual memory settings are below the recommended, this may decrease your computer's performance."  And, then a "Fix It" to fix the problem automatically without having to do it manually.

    What, exactly, does this mean?  I have recently increased my RAM.  I have a Dell computer with XP Home.

  • Anonymous
    February 22, 2006
    Dear,
    I got a message from My OS that I have less virtual Memory. Please tell me what should I do even  my Hard disk is of 80 GB and Ram of 256 MB.

  • Anonymous
    February 23, 2006
    As far as your applications are concerned, the virtual memory can only go to a maximum of 2GB on 32-bit systems. Basically, your virtual memory limit is decided approximately by the
    sum of the RAM + the page file (size) you have set. On 64 bit systems the virtual memory limit is in terabytes, so consider buying 64 bit machines in future.

    Vipin
    Printing/Imaging - MVP
    http://www.graphicshighway.com

  • Anonymous
    February 27, 2006
    Sir,
    I am an MCP working in a corporate environment.The article was really good.
    I have explained the very reasons for more hard drive space and good memory capacity in order to boost speed.
    Hope to read more articles from you.

  • Anonymous
    February 28, 2006
    it is a memory where we stor the runing application which we give less prefrence

  • Anonymous
    February 28, 2006
    Its nice article. Thanks for sharing the knowledge.
    but I did not see any RAM chip that looks like the one in the above picture. :-D.

  • Anonymous
    February 28, 2006
    The comment has been removed

  • Anonymous
    February 28, 2006
    Virtual memory is just a memory that acts as a helper to you RAM. it is a virtual memory that is allocated by the operating system to help it work with applications

    Martin I think you should just keep it managed by the computer this will increase and decrease it according to your needs at different times.

    hope this helps

  • Anonymous
    February 28, 2006
    Can't say. Size of pagefile depends on RAM. Since Martin does not provide this information, the system will decide the size.

  • Anonymous
    March 01, 2006
    Wow!  I haven't seen a memory chip like that in years!  :-)

    Seriously, they are still in use, but so much of the memory most PC users see these days are the SIMM type.

  • Anonymous
    March 01, 2006
    The usual recommendation of Virtual Memory is double the size of your RAM.  If you have 1 gig of RAM, set your virtual memory to 2 gigs.  If you have 512mb RAM, set it to 1 gig.  If you have 4 gigs of RAM, set it to 8 gigs.  That is a nice rule of thumb.  If you plan on doing video compression, go for 3x or 4x.

  • Anonymous
    March 01, 2006
    great stuff to share, helps the average person understand. Thank you

  • Anonymous
    March 01, 2006
    I hear that "more RAM is better". But from what I understand, if the hard disk light isn't lighting all the time, it's not having to store stuff that would be better in RAM.

    Do programs (metaphorically) stretch out and perform better if they have more RAM in which to run?

    P.S.: It's been ages since I've read about computer RAM! Remember the early 80s when everyone was asking what a computer was? :-)

  • Anonymous
    March 01, 2006
    i have heard many differnt setting that one should use regarding virt mem.. and all have one thing in common, how much ram you have installed.  i think the "rule" is typically somewhere between 1.5 to 2 times your physical ram, up to 2Gb.  so for example i have a dell dimension 4700, running windows xp home, sp2, with a 2.8 ghz pent4, with 1gb dual channel ram (i think thats the correct terminology :) ) and i have my virtual memory set for about 1.5 times the size of my ram, s roughly 1.5 GB, but have it spread over 2 partitions... so far i have had no too many problems regarding speed and accessibilty, but who knows perhaps there is a better way and i could be performing at much faster rates.

  • Anonymous
    March 03, 2006
    How do I use the Policy Editor to give my user account and programs I use 'lock memory pages' privileges? I have tried without success after folllowing the instructions in Windows Help and Support. I understand that doing so will allow large memory pages to be used and greatly improve system performance when large memory blocks are allocated.

  • Anonymous
    March 04, 2006
    Very good but it would be nice to know where to go to change the Virtual Memory.

  • Anonymous
    March 04, 2006
    Virtual Memory is a process which requires "memory" to transfer pages to move through you system as you surf or are flipping through websites. The computer recognises pages as they are moved by switching from one page to another. If we imagine how many times we are constantly moveing forward and back and and going from one topic to another the virtual memory store all this info of previous pages transferred through the system. the benefit increases the speed of this process. Low virtual memory creates slower transferr from page /site to another

  • Anonymous
    March 06, 2006
    A virtual memory is called Swapping memory which swaps from virtual memory to hard disk

  • Anonymous
    June 16, 2006
    I guess the question is: how do i make more room for added space. Can i delete or erase info from my virtual memory without damage to my computer? If so, how? I have alot to learn. Thanks for your time.

  • Anonymous
    October 02, 2006
    Hi. I have a 512MB RAM on the computer and have it on "system manage file" but i still keep getting that "low virtual memory" reminder. What should i do? :) Thanks!

  • Anonymous
    December 04, 2006
    virtual memory refers to a technique the operating system uses to help it work with your applications and files.It is also called disk memory.

  • Anonymous
    May 24, 2008
    sir,   i have 2.8 cpu. and i installed 1.5 gb ram. now i can't decide. how much give the memory to virtual memory. pls tell me how much i feed virtual memory  with 1.5 or 2 gb ram.

  • Anonymous
    May 29, 2009
    PingBack from http://paidsurveyshub.info/story.php?title=tiptalk-from-microsoft-at-home-amp-at-work-what-is-virtual-memory

  • Anonymous
    June 01, 2009
    PingBack from http://uniformstores.info/story.php?id=14435

  • Anonymous
    June 18, 2009
    PingBack from http://homelightingconcept.info/story.php?id=185