Skip to main content

Memory and Virtual Memory Management

What is Memory Management?

One of the main functions of Operating systems is Memory Management. Memory Management may be defined as the process of managing the optimal use of main memory that is RAM (Random Access Memory). RAM is much faster than hard disk. So RAM is used to store data and instructions temporarily while they are being executed by CPU ( Central Processing Unit or PROCESSOR ). CPU can get data and instructions from RAM much faster that from hard disk.

As we know CPU is a very very fast device. It may execute billions of instructions per second. CPU will have to wait for data and instruction from hard disk because getting data from hard disk is very slow. That is why RAM is used. So data and instructions needed for execution are brought into main memory that is RAM first. Now RAM provides data and instructions to CPU rapidly.
What is Memory Management

What is Memory Management and virtual memory management

Operating System allocates the required memory are in main memory to programs that are a candidate for execution. The allocated memory area will be de-allocated when the program will finish execution.

What is Virtual Memory?

Some times, main memory that is RAM is not enough to run larger programs. In this case, some operating systems apply the technique of VIRTUAL MEMORY to overcome the problem of small RAM. 

The operating system uses a particular area of hard disk as additional RAM (virtually). The most wanted part of the program in execution may be kept in RAM while the remaining part of that program may on the particular part of the hard disk. This is called Virtual Memory. The area of hard disk used for virtual memory is called a SWAP file. The Swap file is used to exchange data and instructions of a running program between RAM and Hard disk.





Labels:

Comments

Post a Comment

Popular posts from this blog

Types Of Headings In HTML

HTML Hedings Headings in HTML are used to display Titles, Sub-Titles of Sub-Sub-Titles for your web page text. There are six types of headings in HTML. H1 is the largest heading and H6 is the smallest heading. <H1> is opening tag whereas </H1> is the closing tag for the largest heading. The text between <h1> and </h1> will be displayed as the main Title in your web page. Following are the six tags used for six types of headings in HTML. <H1> ... </H1> <H2> ... </H2> <H3> ... </H3> <H4> ... </H4> <H5> ... </H5> <H6> ... </H6> The H1 heading is used for main titles. Actually H1 heading will show the text in largest font size. H2 headings is used for Sub-Titles. H2 displays text in smaller font size than H1, H3 displays text of font size smaller than H1 and H2, and so on. H1 is for largest heading in a text page and H6 is for smallest heading.   Importance Of Headings in SEO H...
Post a Comment
Read more

House Building Expenses Formulas in Excel

Today we will discuss the Excel Worksheet Formulas for recording Monthly House Construction Expense Management . Steps To Create Expense Management Excel Worksheet First of all, start MS Excel with a new workbook. Merge required number of cells in first row of worksheet.               3. Insert Word Art and type a suitable title heading in worksheet.       4. Enter heading row.       5. Enter data in worksheet.       6. Apply the formulas and functions in worksheet as explained later.         Here is the list of expenses we have considered to be recorded. Sr. No Item 1 Cement (Bags) 2 Bricks(Trolly) 3 Sand(Trolly) 4 Gravel(Truck) 5 Iron (Kg) 6 Marble (Square Feet) 7 Electricity Bill 8 Labour 9 Miscelleaneous You can increase this list of expenses accor...
Post a Comment
Read more

Explain different types of storage devices

Topic: Explain different types of storage devices in Computer systems Storage Devices Storage devices are used to store data and instructions permanently. Storage devices are also called secondary storage devices / backing storage devices / external storage devices or auxiliary storage devices. Examples of storage devices include Hard Disk, CD and DVD etc. Why Secondary Storage Devices are Used? Secondary storage devices are used because: Primary memory(RAM) is volatile and temporary. When computer is switched off, all data in ram is erased. Storage devices can store large amounts of data and instructions permanently whereas Primary memory has less capacity of storing data. Types Of Storage Devices There are three main types of storage devices:  Magnetic Tape   Magnetic Disk   Optical Disk   Flash Memory storage devices 1. Magnetic Tape Magnetic tape is the oldest storage device. It is made of plastic coated with m...
3 comments
Read more