Explain a computing environment, Operating System

Assignment Help:

Q. Polling for an I/O completion is able to waste a large number of CPU cycles if the processor iterates a busy-waiting loop several times before the I/O completes. However if the I/O device is ready for service polling can be much more proficient than is catching and dispatching an interrupt. Explain a hybrid strategy that combines sleeping, polling, and interrupts for I/O device service. For every of these three strategies (pure polling, pure interrupts, hybrid) explain a computing environment in which that strategy is more efficient than is either of the others.

Answer: A hybrid approach could switch among polling and interrupts depending on the length of the I/O operation wait. For instance we could poll and loop N times and if the device is still busy at N+1 we could set an interrupt and sleep. This approach would evade long busy-waiting cycles. This process would be best for very long or very short busy times. It would be incompetent it the I/O completes at N+T (where T is a small number of cycles) because of the overhead of polling plus setting up and catching interrupts.

Pure polling is best with extremely short wait times. Interrupts are best with known long wait times.


Related Discussions:- Explain a computing environment

What do you mean by first fit, What do you mean by first fit? First fit...

What do you mean by first fit? First fit allocates the first hole that is big sufficient .Searching can either start at the starting of the set of holes or where the previous f

What are the three main activities of an operating system, What are the thr...

What are the three main activities of an operating system in regard to memory management? Keep track of which parts of memory are now being used and by whom. Decide which pr

What are the various available scheme in ipc, Several schemes available are...

Several schemes available are as follows: Pipes : One-way communication process through which different process can interact. The problem is that the two processes could have

Write a note on multithreading, Write a note on multithreading. Multith...

Write a note on multithreading. Multithreading is the capability of an operating system to execute different parts of a program called as threads, at the same time. The program

Programable clock modes in computer systems, Ask question #Minimuexplain th...

Ask question #Minimuexplain the programable clock modes in a computer system m 100 words accepted#

Operating systems structures, with the aid of diagrams describe the followi...

with the aid of diagrams describe the following OS structure monolithic,layered and client server.

How can the deadlock be prevented-safe state, How can the deadlock be preve...

How can the deadlock be prevented-Safe State Safe state : A state is safe if the system is able to allocate resources to each process in some order and still avoid deadlock.

Explain process scheduling, Explain Process scheduling Process scheduli...

Explain Process scheduling Process scheduling consists of the subsequent sub-functions: 1.      Scheduling : Selects the process to be implement next on the CPU 2.      D

Is disk scheduling useful in a single-user environment, Is disk scheduling,...

Is disk scheduling, other than FCFS scheduling, useful in a single-user environment? Explain your answer. In a single-user environment, the I/O queue usually is blank. Requests

Requirements for solution of critical section problem, What are the require...

What are the requirements for solution of critical section problems? Mutual exclusion : If process p is implementing in its critical section then no other processes can be exe

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd