Week 3: Clear

         The concept that was most clear to me this week was virtual memory. Virtual memory is a form of memory management to optimize the use of RAM. Multitasking can result in running out of physical memory, so the computer takes part of the hard drive and allocates it as a swap file, pretending it is an extension of the physical memory. The virtual memory is divided into fixed-size units called PAGES, some of which are on the disk and some of which are in the memory. The process of transferring a page between memory and storage is called swapping. Copying from virtual memory into physical memory chips is called SWAP IN, while the opposite process (from memory to storage) is called SWAP OUT. Virtual memory makes the computer's memory seem larger than it actually is by utlizing storage as additional memory. There is a tradeoff with virtual memory: although it enables oversized applications, it works slower than physical RAM.
        Virtual memory is important in the business environment because computers with this operating system use hardware memory more efficiently than computers without virtual memory and also make application programming easier. This integral part of the computer is important for optimizing memory allocation. Without the virtual memory, computers would easily run out of memory because they would not have enough physical RAM.
           This website clearly explains the concept of virtual memory.  It discusses how the virtual memory works and talks about configuring the virtual memory. I like the picture on this website that shows memory management between the CPU, cache, RAM, and virtual memory as part of disk storage. I also found this video interesting since it explains how to increase performance with the virtual memory.  Here is a pyramid visualization of the memory hierarchy:

Works Cited:

http://computer.howstuffworks.com/virtual-memory.htm

http://www.youtube.com/watch?v=L2igH6O0ARM

http://static.howstuffworks.com/gif/computer-memory-pyramid.gif