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

Explain about operating system services, Q. Explain about Operating System ...

Q. Explain about Operating System Services? An operating system offers services to programs and to users of those programs. It provided by one environment for execution of

What is a two state process model?, What is a two state process model? ...

What is a two state process model?   At any time a process is being implementing by a processor or not. Therefore a process may be in Running or not running state. When an Ope

What is the use of fork and exec system calls, What is the use of fork and ...

What is the use of fork and exec system calls? Fork is a system call by which a latest process is created. Exec is also a system call, which is used after a fork by one of the

Micro operation, Ask question maxmum words accepted#

Ask question maxmum words accepted#

Define server processing with queues, Define Server Processing with Queues ...

Define Server Processing with Queues The efficient server processing of client request is essential for optimized client- server applications. This process is greatly enhanced

Evaluate the physical address, Compare between the one and two-dimensional ...

Compare between the one and two-dimensional memory organizations in terms of the  memory structure,  advantages, and disadvantages.  Which approach would better support the needs o

Nested Macro calls, . Nested Macro calls are expanded using the

. Nested Macro calls are expanded using the

What are turnaround time and response time, What are turnaround time and re...

What are turnaround time and response time? Turnaround time is the interval among the submission of a job and its completion. Response time is the interval among submission

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