Major Functions of Operating Systems - Computer Information

Latest

Feb 26, 2009

Major Functions of Operating Systems

The major functions of an OS are:

-resource management,
-data management,
-job (task) management, and
-standard means of communication between user and computer.

The resource management function of an OS allocates computer resources such as CPU time, main memory, secondary storage, and input and output devices for use.

The data management functions of an OS govern the input and output of the data and their location, storage, and retrieval.

The job management function of an OS prepares, schedules, controls, and monitors jobs submitted for execution to ensure the most efficient processing. A job is a collection of one or more related programs and their data.

A job is a collection of one or more related programs and their data.

The OS establishes a standard means of communication between users and their computer systems. It does this by providing a user interface and a standard set of commands that control the hardware.

Typical Day-to-Day Uses of an Operating System

-Executing application programs.
-Formatting floppy diskettes.
-Setting up directories to organize your files.
-Displaying a list of files stored on a particular disk.
-Verifying that there is enough room on a disk to save a file.
-Protecting and backing up your files by copying them to other disks for safekeeping.

How Do Operating Systems Differ?

Operating systems for large computers are more complex and sophisticated than those for microcomputers because the operating systems for large computers must address the needs of a very large number of users, application programs, and hardware devices, as well as supply a host of administrative and security features.

Operating system capabilities can be described in terms of

-the number of users they can accommodate at one time,
-how many tasks can be run at one time, and
-how they process those tasks.

Number of Users:

A single-user operating system allows only one user at a time to access a computer.

Most operating systems on microcomputers, such as DOS and Window 95, are single-user access systems.

A multiuser operating system allows two or more users to access a computer at the same time (UNIX).

The actual number of users depends on the hardware and the OS design.
Time sharing allows many users to access a single computer.
This capability is typically found on large computer operating systems where many users need access at the same time.

Number of Tasks

An operating system can be designed for single tasking or multitasking.

A single tasking operating system allows only one program to execute at a time, and the program must finish executing completely before the next program can begin.

A multitasking operating system allows a single CPU to execute what appears to be more than one program at a time.

Context switching allows several programs to reside in memory but only one to be active at a time. The active program is said to be in the foreground. The other programs in memory are not active and are said to be in the background. Instead of having to quit a program and load another, you can simply switch the active program in the foreground to the background and bring a program from the background into the foreground with a few keystrokes.

Cooperative multitasking in which a background program uses the CPU during idle time of the foreground program. For example, the background program might sort data while the foreground program waits for a keystroke.

Time-slice multitasking enables a CPU to switch its attention between the requested tasks of two or more programs. Each task receives the attention of the CPU for a fraction of a second before the CPU moves on to the next. Depending on the application, the order in which tasks receive CPU attention may be determined sequentially (first come first served) or by previously defined priority levels.

Multithreading supports several simultaneous tasks within the same application. For example, with only one copy of a database management system in memory, one database file can be sorted while data is simultaneously entered into another database file.

105 comments:

  1. I like the info provided it has been very helpful

    ReplyDelete
  2. NICE EXPLANATION; BRIEF AND SIMPLE, BUT COMPREHENSIVE.

    ReplyDelete
  3. This is realy a strong helping hand, thanks so much.

    ReplyDelete
  4. Really it's very useful as well as helpful fr the learners....!

    ReplyDelete
  5. operating system is a interface between user and system

    ReplyDelete
  6. A great information on OS.....Thankful to u

    ReplyDelete
  7. give me informtion abuot computer opertaing syste,

    ReplyDelete
  8. mmm not indepth enough go into more Details i believie you left out Network Management (internet/local computerlink)

    ReplyDelete
  9. This comment has been removed by a blog administrator.

    ReplyDelete
  10. Found it rather shallow though has assisted a great deal.

    ReplyDelete
  11. I love it, what a great explaination keep it up

    ReplyDelete
  12. thanx for the explanation

    ReplyDelete
  13. that was really very helpful....

    ReplyDelete
  14. LOVE IT!!!!!!!!!!!!!

    ReplyDelete
  15. very good for knowlage.....

    ReplyDelete
  16. wow that was great never really understood the resource management function till i visited this place thanks soo much

    ReplyDelete
  17. This is great information explain about the operating systems. It's all feature and advantage is amazing for customers.


    web conferencing

    ReplyDelete
  18. useful for my project

    ReplyDelete
  19. got an assignment, thanks for the informatiom.

    ReplyDelete
  20. Aq. From adamawa state university mubiJuly 18, 2012 at 5:24 PM

    Very nice explanation

    ReplyDelete
  21. u are very helpful

    ReplyDelete
  22. Thanx 4 great info about os

    ReplyDelete
  23. its very useful for d learners...

    ReplyDelete
  24. Thanks.. very helpful writing

    ReplyDelete
  25. i love d works, but need some improvmets...tanks!

    ReplyDelete
  26. wonderful information, thnk u very helpful

    ReplyDelete
  27. Thanks for this beautiful help..........

    ReplyDelete
  28. cool job, well done

    ReplyDelete
  29. very clear xplanation i like it

    ReplyDelete
  30. Easy to understand. Great work!

    ReplyDelete
  31. wow i like it

    ReplyDelete
  32. It has really helped me. Thanks so much

    ReplyDelete
  33. A lot of us who are under constant pressure tend to eat too much and do
    not take good care of their bodies. Men can follow these health and fitness tips to lose weight and get
    healthy and fit. Remember; there is a difference between a fattening diet and a healthy diet.


    My page - http://team-6.eng.toyo.ac.jp/

    ReplyDelete
  34. Hi there to every , as I am in fact eager of reading this websiteís post
    to be updated regularly. It contains nice material.


    My weblog - scouted.co.za

    ReplyDelete
  35. To subscribe, visit the magazine's web site and click on their 'subscribe' button. Skiing and snowboarding are strenuous sports which demand a lot of endurance, so your usual set of ten to fifteen reps really isn''. Menopause weight gain is not inevitable, but it can be more difficult to maintain a healthy weight as your metabolism slows.

    Here is my web page - http://fitnesstipsonly.com/post/41318051117/daily-worko ut-plan

    ReplyDelete
  36. It's going to be ending of mine day, except before ending I am reading this fantastic post to increase my knowledge.

    Here is my page :: Biotechnology Careers

    ReplyDelete
  37. Or maybe you look at it from a monetary standpoint and decide that Guy Ritchie and Madonna divorce
    was worse because they were married so long and have
    children and there is a lot of money involved.
    Stay connected with for the latest tit-bits of pick me up news
    and cool celebrity pictures. instantly and cannot wait for magazines then celebritynewsapp is the best available source which
    keeps on updating instantly.

    Visit my web-site; latest celeb news

    ReplyDelete
  38. One can find plenty of funny pictures and videos by a single click
    on any search engine like Yahoo or Google.
    That is why we have dedicated this page to help you renew your
    spirit and perhaps have a few laughs too. The moment you think of funny video the first name that probably comes to your
    mind is You - Tube.

    Here is my blog; very funny pictures and cartoons

    ReplyDelete
  39. choose numerous softwares that are capable enough to
    satisfy your necessities. If you have wandered around the internet to
    any extent you have probably encountered funny pictures.
    While almost every cat is a work of aesthetic
    beauty, they are often animals that combine silliness and a fierce disposition.


    Here is my homepage :: emi-lvh.jbcourse.com

    ReplyDelete
  40. So, before you play, make sure you stretch the
    muscles used in swinging your golf club. Protein has a number of benefits, including increasing your metabolism.

    If you have never exercised in the morning, then we urge you to
    try it at least for one week.

    Feel free to visit my web-site; fitness tips and quotes

    ReplyDelete
  41. very interesting and eye opener .
    Thank you guys for your comments
    fm zimbabwe

    ReplyDelete
  42. Good but I am also need some references as to authentic university assignments
    fm zimbabwe

    ReplyDelete
  43. There's certainly a great deal to find out about this subject. I like all of the points you've made.



    Here is my web page :: calories burned walking

    ReplyDelete
  44. Remarkable! Its in fact awesome piece of writing, I have got much clear idea concerning from this paragraph.


    My page: calorie burn calculator

    ReplyDelete
  45. Can I simply say what a relief to uncover someone
    who really understands what they're discussing over the internet. You certainly realize how to bring an issue to light and make it important. More people have to read this and understand this side of your story. I can't believe you aren't more popular since you definitely have the gift.

    Visit my weblog; airplanes games

    ReplyDelete
  46. Hello everybody, here every person is sharing these familiarity,
    thus it's fastidious to read this webpage, and I used to pay a visit this blog everyday.

    Also visit my website: raspberry ketones

    ReplyDelete
  47. Hello my loved one! I want to say that this post is awesome, great written and come with approximately all
    significant infos. I would like to see more posts like this .


    Stop by my website ... appliance repair Valrico

    ReplyDelete
  48. Hello everуone, it's my first visit at this web site, and post is truly fruitful designed for me, keep up posting these posts.

    My web-site; hemroids

    ReplyDelete
  49. Very nice post. I just stumbled upon your weblog and wished to say that I have really enjoyed surfing around your
    blog posts. In any case I'll be subscribing to your rss feed and I hope you write again soon!

    Feel free to surf to my web blog - bowtrol colon cleanser review

    ReplyDelete
  50. Tremendous issues here. I am very satisfied to look your article.

    Thanks a lot and I'm taking a look ahead to contact you. Will you please drop me a mail?

    Take a look at my homepage - saffron extract where to buy

    ReplyDelete
  51. This comment has been removed by the author.

    ReplyDelete
  52. I really like your blog.. very nice colors & theme.
    Did you design this website yourself or did you hire someone to do it for you?

    Plz answer back as I'm looking to create my own blog and would like to know where u got this from. many thanks

    Feel free to visit my page - house painter

    ReplyDelete
  53. Hello there, just became alert to your blog through Google, and found that it's truly informative. I am gonna watch out for brussels. I will be grateful if you continue this in future. Many people will be benefited from your writing. Cheers!

    Also visit my web page master cleanse weight loss ()

    ReplyDelete
  54. Αn intеresting diѕcuѕsion іs definitely woгth commеnt.

    I do think thаt уοu οught to
    wгite more on this ѕubject, іt might not be a taboo matteг but
    usuallу peoplе don't speak about such subjects. To the next! Best wishes!!

    Here is my web site :: die-abnehmloesung.de

    ReplyDelete
  55. superbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb

    ReplyDelete
  56. Very informative and well written post! I would suggest this blog to my friends also

    Samsung - NP900X3A 13.3 LED Notebook - Intel Core i5 i5-2467M 1.60 GHz

    ReplyDelete
  57. thanks for your information

    ReplyDelete
  58. WOW!! terribly informative web log and helpful techniques. Please visit this web site if you wish a lot of detail
    IT service providers Indianapolis

    ReplyDelete
  59. Hi there, I enjoy reading all of your post. I wanted to write a little comment
    to support you.

    Also visit my web blog - testosterone booster for men

    ReplyDelete
  60. These tips and information are provide very help about computer services.Thanks for posting.

    Thin Clients & Zero Client

    ReplyDelete
  61. I found this answer very much helpful

    ReplyDelete