Virtual Memory vs Page File

Using virtual memory is a common approach to operating systems. This is because it provides a lot of advantages at low cost. As you know each computer has a memory (RAM), which have all running programs. Each process takes their part of the memory and if you open too many programs it can do. Here comes the virtual memory support.

By using virtual memory, regular parts of your RAM that you have not used recently are recorded on the hard disk. Thus frees up space in RAM memory for new programs. The transfer of parts from memory and recording them on the hard disk automatically and is managed by the operating system. Thanks to virtual memory, you have a lot more memory than as your real RAM. Obtained much more efficient use of RAM, only the most accessible parts of it actually remains on it and transfer of unused hard disk. If a process is requested information located on the hard disk, it is transferred to memory. If no empty memory, the portion of employees transferred to the hard disk.

What is Page file (page file)?

The hard disk where this information is recorded is called the Page file (page file). The name comes from the word page (page). When using virtual memory, real memory is divided into equal-sized sections called pages. These are pieces of information to be transferred. The idea of ??virtual memory is that each program thinks it has more memory than it actually is free. Use virtual addresses that are different from the real addresses in memory. Thus two different processes can operate with the same virtual addresses. Later they are converted to different real addresses. That is, the programs work with virtual addresses and real hardware. To convert a virtual address is used in a real page table (page table). This table contains information that associates each virtual page and address in real memory or address in the Page file (page file).

Where should be the Page file (page file)?

For faster operation of virtual memory Page file should be readily accessed by the head of the hard disk. If you have one hard drive, place the file in the Page Title, which has the most activity, ie they are installed programs. There is the chance for a head on the hard disk most of the time. If you have more than one hard disk, place the file in the Page in which no operating system is installed and in which there is not much activity. Thus, where once the file is accessible chapters of this hard drive will remain there and are ready to access it quickly.

What should be the size of the Page File?

It is often debated question. Unfortunately the answer is very simple and unambiguous. Many times I’ve seen it recommended size is 1.5 or 2 times the amount of RAM. Also minimum and maximum sizes are the same so as not to delay receiving a change of its size.