About Virtual Memory in Windows

moisesCujardo · July 2008

To All,

I have a question regarding Virtual Memory in Windows.
If I'm not mistaken VM is a supplement of RAM? My question is,
is it separated on a separate partition in Windows? or is it just part
or located say on the partition where you have installed the Windows
System...???

I have heard that VM is much like the SWAP in Linux, and in Linux
the SWAP could be on a separate partition, am i right with that one?

I'm confident that you guys can clear things out to me, so, thank you
in advance... I'm asking this because, I am planning of taking up the
A+ Exams and I wanted to expand my knowledge.

Thank you all

moisesCujardo

somedudefromthenet · July 2008

Nice to hear that you plan to take the test!

Yes you are correct in relation with how Linux can manage RAM swaps. However with Windows it is a file located on (by default) the system partition and can be relocated to different partitions/drive volumes.

Windows is also able to allocate free space on multiple volumes for use as a swap/paging file.

astorrs · July 2008

You can think of the pagefile (pagefile.sys in the root of c:\ on a default Windows installation) as analogous to the SWAP partition in Linux. Both are used to provide memory above and beyond the physical limitations of the computer (the amount of physical RAM installed), but the internal mechanisms are quite different.

Every process running in Windows thinks it has 2GB of memory allocated just to itself (this is assuming a default 32-bit installation) and the pagefile is used to swap memory out of RAM to disk so that the most active pieces are always running from RAM (since RAM speeds are like 1000 times faster than disk speeds). An operating system without a virtual memory manager is limited to the amount of physical RAM installed and as such doesn't have the flexibility of a modern O/S.

whistler · July 2008

moisesCujardo wrote:

To All,

I have a question regarding Virtual Memory in Windows.
If I'm not mistaken VM is a supplement of RAM? My question is,
is it separated on a separate partition in Windows? or is it just part
or located say on the partition where you have installed the Windows
System...???

I have heard that VM is much like the SWAP in Linux, and in Linux
the SWAP could be on a separate partition, am i right with that one?

A swap file can be either on the same disk as system root(windows) or on a seperate partition. Unlike Linux where it is a completely seperate partition, and they are similar in nature(but don't say that in front of a Linuxer). The guidelines and suggestions are. A small swap file on the same drive as system root, for memory **** etc., and then on a seperate hard drive a larger swap file. This is to allow the swapping to occur more efficiently and faster. THe swap file is located at the root of the hard drive/partition where ever it is assigned(ex.. C:\Pagefile.sys).

I'm confident that you guys can clear things out to me, so, thank you
in advance... I'm asking this because, I am planning of taking up the
A+ Exams and I wanted to expand my knowledge.

Thank you all

moisesCujardo

moisesCujardo · July 2008

wow, thank you all for the replies. It really clear things out to me!!!

I have also noticed this, one time i got a prompt stating that Your Virtual
Memory Is Low. It was said that VM, is a paging file in Windows usually
located on the Drive C. When I got the message, "Your Virtual Memory is
Getting Low", I've noticed then that my Drive C runs out of space.

Having said that, I am assuming that VM is depending on the Disk Space
where it is on, say for example on Drive C. Unless of course you specify it
by yourself... Ahm is that a correct observation?

FYI, I'm really signing up on this site. Knowing that there are a lot
of technically good people who are willing to share their knowledge to
newbies such as me... Thanks Guys...

mois

astorrs · July 2008

moisesCujardo wrote:

I have also noticed this, one time i got a prompt stating that Your Virtual
Memory Is Low. It was said that VM, is a paging file in Windows usually
located on the Drive C. When I got the message, "Your Virtual Memory is
Getting Low", I've noticed then that my Drive C runs out of space.

Having said that, I am assuming that VM is depending on the Disk Space
where it is on, say for example on Drive C. Unless of course you specify it
by yourself... Ahm is that a correct observation?

The pagefile by default these days starts off at a certain size and grows as needed, it probably attempted to grow but realized that you were running out of space on the drive it was located on (in your case C:\) and threw the error message.

Be aware this message can also be a red herring of sorts, as lots of other problems can manifest themselves in similar ways (but in your stated case it sounds dead on).

Oh and welcome to the forums.

moisesCujardo · July 2008

Thank you guys for the reply and the knowledge that you've shared!!!!

About Virtual Memory in Windows

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