What is virtual memory?

Question

What is virtual memory? and how does it get lower?
and What is physical memory?
I have a Gta game. When I play this game, a blue page appears and there is written "physical memory dump".

Answer 1

Virtual memory uses cheaper (and slower) hard disk space to augment physical chip memory. This means you can run more applications than you could with physical memory alone. The more apps you run, the less physical memory you'll have available and the more virtual memory will be used - and so the system will slow down.



Anyhoo, the blue screen is likely overheating (if it never occurs in non-game activity, such as word processing) or a dodgy graphics driver.

The former can be rectified in the short-term by taking the side off of the PC (assuming not a laptop) and in the long term by adding better cooling (fans, etc). The latter may be solved with uninstall of drivers followed by installation of newer drivers.

Answer 2

Physical Memory is an array of integrated circuts or ICs. Programs you run are loaded into physical memory and run from there. If the program is larger than the amount of physical memory you have, a portion of it will load into virtual memory. Virtual memory is a file on your hard drive and is called a swap file. The swap file should be a minimum of 1.5 times the physical memory size and is adjustable. We set our clients up at twice the physical memory size and a max of 4 times. "Pages" are swapped between those two locations as needed. Programs see only memory and make no distinction between physical or virtual memory. To adjust physical memory size in Windows XP click on Start, then right click on My Computer or if My Computer is on the desktop just right click on the My Computer icon, left click on properties, left click on the advanced tab, left click on the performance settings button, click on the advanced tab in the new window, then click on change in the Virtual memory . Click on custom size and type in some numbers.



Memory, and eventually virtual memory, gets lower this way. Programs go to the operating system and ask to borrow some memory so they can perform some function. The operating system agrees and lends the program the memory it needs for an indefinate period of time but the program must return the memory to the operating system when it is through with it. If the program keeps borrowing memory but never returns it (that's called a memory leak) then eventually the system runs out of memory. It usually warns you first.



Dan / http://PCWebDoc.com

Answer 3

Today application is getting bigger and bigger. Therefore, it requires a bigger system memory in order for the system to hold the application data, instruction, and thread and to load it. The system needs to copy the application data from the HDD into the system memory in order for it to process and execute the data. Once the memory gets filled up with data, the system will stop loading the program. In this case, users need to add more memory onto their system to support that intense application. However, adding more system memory costs the money and the normal user only needs to run the the intense application that requires the memory only for one or two days. Therefore, virtual memory is introduced to solve that type of problem.





Terminology & Explanation



There are two types of memory, which are as follows:



* System Memory(Physical memory) is a memory that is used to store the application data and instruction in order for the system to process and execute that application data and instruction. When you install the memory sticks to increase the system RAM, you are adding more system memory. System Memory can be known as either the physical memory or the main memory.



* Virtual Memory is a memory that uses a portion of HDD space as the memory to store the application data and instruction that the system deemed it doesn't need to process for now. Virtual Memory can be known as the logical memory, and it controls by the Operating System, which is Microsoft Windows. Adding the Virtual Memory can be done in system configuration.





Tutorial Information & Facts or Implementation



Virtual Memory is a HDD space that uses some portion of it as the memory. It is used to store application data and instruction that is currently not needed to be process by the system.



During the program loading process, the system will copy the application data and its instruction from the HDD into the main memory (system memory). Therefore the system can use its resources such as CPU to process and execute it. Once the system memory gets filled up, the system will start moving some of the data and instruction that don't need to process anymore into the Virtual Memory until those data and instruction need to process again. So the system can call the next application data and instruction and copy it into the main memory in order for the system to process the rest and load the program. When the data and instruction that is in the Virtual Memory needs to process again, the system will first check the main memory for its space. If there is space, it will simply swap those into the main memory. If there are not any space left for the main memory, the system will first check the main memory and move any data and instructions that doesn't need to be process into the Virtual Memory. And then swap the data and instruction that need to be process by the system from the Virtual Memory into the main memory.



Having too low of Virtual Memory size or large Virtual Memory size (meaning the size that is above double of the system memory) is not a good idea. If you set the Virtual Memory too low, then the OS will keep issuing an error message that states either Not enough memory or Virtual too low. This is because some portion of the system memory are used to store the OS Kernel, and it requires to be remain in the main memory all the time. Therefore the system needs to have a space to store the not currently needed process data and instruction when the main memory get filled up. If you set the Virtual Memory size too large to support the intensive application, it is also not a good idea. Because it will create the performance lagging, and even it will take the HDD free space. The system needs to transfer the application data and instruction back and forth between the Virtual Memory and the System Memory. Therefore, that is not a good idea. The ideal size for the Virtual Memory is the default size of Virtual Memory, and it should not be exceed the value of the triple size of system memory.



To determine how much virtual memory you need, since the user's system contains the different amount of RAM, it is based on the system. By default, the OS will set the appropriate size for Virtual Memory. The default and appropriate size of Virtual Memory is:



CODE

* 1.5 =

.



For example, if your system contains 256 MB of RAM, you should set 384 MB for Virtual Memory.



CODE

256 MB of RAM (Main Memory) * 1.5 = 384 MB for Virtual Memory





If you would like to determine how much the Virtual Memory is for your system and/or would like to configure and add more virtual memory, follow the procedure that is shown below. The following procedure is based on windows XP Professional.



1-1) Go to right-click My Computer and choose Properties



1-2) In the System Properties dialog box, go to Advanced tab



1-3) Click Settings button that is from the Performance frame

Answer 4

Your system has x amount of semiconductor memory in a form of a module. This is physical memory. Your computer has many things going on at one time (windows is a multitasking operating system). When you run out of memory, the system takes idle programs and their contents and stores them on the hard drive in what is called a "swap file" that is virtual memory. All this happens in microseconds which makes it important to be able to transfer data to and from the hard drive as quickly as possible to make it seem that there is little or no delay in program execution.