UGC NET CSE | June 2007 | Part 2 | Question: 37

Question

Windows is a _______ operating system:

• A. Non-preemptive
• B. Preemptive
• C. Multi-user
• D. Real time

Comments

multi user means more than one user can be created . computer is not multi user windows operating system is

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I am confused between b and c,in order to choose one option i choose C over B.

In widows we do multitasking which is done by Round robin ,so obviously Preemption is there.

Windows is definitely multi user(In case they rae not referring to initial versions of window)

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@Sanjay Sharma

So, sir is there any valid answer here now?

I am sure about BCD.

Answer 1

According to me (Because the question is ambiguous) I would select Multi-user Because

A multi-user operating system is an operating system that allows multiple users on different computers or terminals to access a single system with one OS on it. These programs are often quite complicated and must be able to properly manage the necessary tasks required by the different users connected to it. The users will typically be at terminals or computers that give them access to the system through a network, as well as other machines on the system such as printers. A multi-user operating system differs from a single-user system on a network in that each user is accessing the same OS at different machines.

This family of OS has multi-user support Windows (NT/2000/XP/Vista) 

We can also choose Real Time OS because

Windows does have a Windows Embedded family of products as Embedded Compact, formerly Windows Embedded CE and Windows CE,

I never heard like "I need a preemptive or non-Preemptive OS to do a particular task " .But you have definitely heard that we need a real time OS or Multi user OS (for online gaming ) so I would not choose these options. (just a common sense)

Answer 2

My answer is preemptive . The reason is that , currently all versions of windows including 7, 8 and 10 and windows servers also are preemptive which use windows NT kernel. But multi user (meaning many users accessing the computer at same time) is not supported in all of the editions of all versions of windows. Even if windows supports multiuser in many systems , then it will have to be preemptive to provide same resources to many users at same time on single processor.

Answer 3

Non-Preemptive Scheduling - When a task runs until it stops (voluntarily), or finishes. Windows had Non-Preemptive Scheduling till Windows 3.x, after which it changed to Preemptive from Windows 95.

Preemptive Scheduling - Where a task can be forcibly suspended by a CPU interrupt, unlike Non-Preemptive where the task runs until it releases control of the CPU.

Most modern operating systems are pre-emptive. Nearly all versions of Windows( from Windows 95 - Windows 10 including Windows NT) are pre-emptive.

Multi-user software is software that allows access by multiple users of a computer. Time-sharing systems are multi-user systems. Most batch processing systems for mainframe computers may also be considered "multi-user", to avoid leaving the CPU idle while it waits for I/O operations to complete. However, the term "multitasking" is more common in this context.

Some multi-user operating systems such as Windows versions from the Windows NT family support simultaneous access by multiple users (for example, via Remote Desktop Connection) as well as the ability for a user to disconnect from a local session while leaving processes running (doing work on their behalf) while another user logs into and uses the system. The operating system provides isolation of each user's processes from other users, while enabling them to execute concurrently

So,Windows is Multi-User based.

A real-time operating system (RTOS) is an operating system (OS) intended to serve real-time applications that process data as it comes in, typically without buffer delays. Processing time requirements (including any OS delay) are measured in tenths of seconds or shorter increments of time. A real time system is a time bound system which has well defined fixed time constraints. Processing must be done within the defined constraints or the system will fail. They either are event driven or time sharing. Event driven systems switch between tasks based on their priorities while time sharing systems switch the task based on clock interrupts.

Windows CE is a Real-Time OS.

Comments

But I think the most appropriate answer should be non-preemptive. This is because if you talk about real time software and hardware both comes into picture and if you think multiuser it means windows can be acessed by multiple users at the same time and it is also dependent on the virtual machine specialization. Please correct me if I am wrong

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Current versions of Windows are not pre-emptive.. hence we can omit or leave the option

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Current version of windows is preemptive as we can switch from one process to another process leaving the previous element at its older position

Answer 4

option c is more appropriate because

option a is wrong due to their is no such strict boundation to perform task in particular time 

option b is wrong due to at a single time instance multiple user not used same system

option c is correct  due to multitasking and is achieved via Preemption

option d is wrong due to if it non Preemptive  then multitasking not achieved

Comments

Yes. And there are system user who runs privileged jobs.

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But in this case one need to signout then another get a chance to use it

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Signout doesn't mean a user is not running jobs or when signed out all jobs are getting killed. I don't know more as I haven't seen windows for years but know that this is similar to Linux. In Linux users command lists all users currently logged in and top command lists all processes some of which belong to different users.