For applications that need more memory than provided by
the original factory installed memory, additional RAM should
be installed. It is also possible to use the hard disk as a virtual
memory when the application needs more memory than the
available physical memory. In such cases, however, the data
access speed will be substantially lower than that achieved
using RAM. For example, the data access time using virtual
memory could be as high as 160,000 times more than that
using RAM [2]. In utilizing virtual memory, the CPU needs
to page the data to from a swap file in the hard disk
designated for virtual memory. This routine leads to a
slowed-down processing of the application. In other words,
the CPU utilization for application processing is not one
hundred percent.