What is Virtual Memory ?

We believe, human are creator of all Definition of computer System. So we must have brought above word from our life. Let’s analyze and find out the correct explation of VIRTUAL MEMORY.

Think, we have given a task to wish our friends in their birthday. And we have 40 friends. Their birth day comes every month of the year but we can not remember more than 5 birth day (it’s constrain since we have lot of work to do). This task supposed to continue all the coming years of our life.

Now, the question is how we can execute the task without fail.


First, the entire friend’s birthday need to written in our diary, record or anywhere. It should be in form of hard copy. So that it persists for long years. Neither it can be erased nor evaporate because it’s a durable.


Second, Arrange all the birth day according to its month. So on an average 40/12= 4 (round figure). It means, we need to memorized 4 person’s birth day in every month. It is possible to remember 5 birth days.

Third, let’s memorized or bring 4 birth days into human memory from diary or record on 1st day of every month. Now, 4 coming birth day are in human memory and we can wish them in time when it comes.

In this way we can wish all our friends birth day in time with out fail.

Observation

1. Human memory is neither a note book nor a hard disk. So the information stored in human memory in a virtual manner. It can erased or disappear after a month.
2. Data 40 birth day is quite high to fit into human memory since we can remember only 5 birthdays.
3. If we remember some ones birthday then only we can wish them in time. So to remember we need to refresh each month.

Conclusion.

1. First step, 40 birthdays in a record is called Secondary Memory. Birthday in human memory is called virtual (memory).
2. Second Step, Arrange in particular order is an algorithm to sort the birthdays.
3. Third, To memorize in every monthis called scheduling.

Advantage.

1. Always virtual memory is faster than the Secondary memory. You can say someone's birth date if it was in your memory than refering hard copy. Because it always take a while to recall if something is in human memory.
2. No need to remember all the 40 birth days. It save memory space for other purpose.
3. If we remember 40 birthday then what is use to remember the birthdays which comes on DEC. It unnecessaliy occupie the memory.



“Virtual memory is a technique that allows the execution of process that is not completely in memory”.

"Virtual Memory involves the separation of logical memory as perceived by users from phyical memory. This separation allow an extremely large virtual memory to be provided for programmers when only a smaller physical memory is avalible."
Phycial Memory – Random Acceess Memory.