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

Starvation, what do you mean by starvation?explain in detail

what do you mean by starvation?explain in detail

Comparison of disk scheduling algorithms, COMPARISON OF DISK SCHEDULING ALG...

COMPARISON OF DISK SCHEDULING ALGORITHMS Name      Description                  Remarks      (Selection according to requestor)   RSS        Random scheduling     fo

Safety algorithm and resource request algorithm, Safety algorithm : This is...

Safety algorithm : This is to make sure if the system is in safe state or not. It may need an order of m x n2 operation to determine if the state of the system is safe or not.

System protection, what is the need-to-know principle? why is it important ...

what is the need-to-know principle? why is it important for a protection system to adhere to this principle?

Explain fixed partitioning, Explain fixed partitioning. Partitioning ar...

Explain fixed partitioning. Partitioning are the simpler techniques that don't involve virtual memory. Partitioning has been used in numerous variations in operating systems.

Dual Mode Operation, I am not getting what you have tried to describe here....

I am not getting what you have tried to describe here. Can you elaborate more about this, i will be thankful to you. Vinay

Define the executor (worker thread), Define the Executor (Worker Thread)  ...

Define the Executor (Worker Thread)  The responsibility of the Executor (or Worker Threads) is to execute instructions on behalf of a client-server connection. The Executor mus

Recognition of essential syntactic constructs by reductions, Recognition of...

Recognition of essential syntactic constructs by reductions, this task is carried out by Recognition of essential syntactic constructs by reductions, this task is carried out

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