What is pagefile?
RAM(Random Access Memory) is a limited resource, whereas virtual memory in most practical purposes is a unlimited resource. There can be many processes, each one having its own 2 GB of private virtual address space. When the memory that is in use by all the existing processes exceeds the amount of available RAM, the operating system moves pages (4 KB pieces) of one or more virtual address spaces to the hard disk, thus freeing the RAM frame for other uses. In windows systems, these “paged out” pages are stored in one or more files that are named pagefiles.sys in the root of a partition. There can be one such file in each disk partition. The location and size of the page file is configured in Control Panel.
How to set these values for the page file?
Click System, click Advanced system settings, and then click Settings under Performance.
How big should I make the pagefile?
There is no single answer to this question because it depends how much RAM is installed and how much virtual memory that workload requires. If there is no other information available, the typical recommendation of 1.5 times the amount of RAM that is in the computer.
How to configure pagefile on servers?
On server systems, a common objective is to have enough RAM so that there is never a shortage and so that the pagefile is essentially not used. On these systems, having a very large pagefile may serve no useful purpose. On the other hand, disk space is usually plentiful, so having a large pagefile (for example, 1.5 times the installed RAM) does not cause a problem and eliminates the concern about how large to make it.
In other operating systems, the pagefile is called a swap file or a swap partition.
