How to access the disk data, Computer Engineering

Assignment Help:

Q. How to Access the Disk Data?

Disks operate is semi-random mode of operation and generally referenced block wise. The data access time on a disk comprises two major components:

  • Seek time: Time to position head on a particular track. On a fixed head disks it's time taken by electronic circuit to select needed head whereas in movable head disks it's time needed to move head to a specific track.
  • Latency time: This is time needed by a sector to reach below read/write head. On an average it's half of time taken for a rotation by disk.

In addition to seek and latency time the time taken to transfer a (read/write) block of words can be considered however normally it is too small in comparison to seek time and latency and in general disk access time is concerned to be sum of seek time and latency time. Because access time of disks is large so it is advisable to read a sizeable part of data in a single go and so disks are referenced block wise. As a matter of fact you will find that in most of computer system input/output involving disk is given a very high priority. Fundamental reason for such priority is latency time which is needed once the block which is to be read passes below read-write head. It may take time of order of milliseconds to do it again, in turn delaying Input /Output and lowering performance of system.


Related Discussions:- How to access the disk data

Explain the typical functions of operating systems, List the typical functi...

List the typical functions of operating systems. Classical functions of operating system are given as: (1) Process management: A process is a program throughout execution.

Usb communication - computer architecture, Data packets: USB communica...

Data packets: USB communication takes the form of packets. Originally, all packets are sent from the host, using the root hub and possibly more hubs, to components. Some of th

Describe big notation, Q. Describe Big Notation? Big O Notation : The ...

Q. Describe Big Notation? Big O Notation : The set O (g(n)) comprises all functions f(n) for that there exists   positive constants c such that for satisfactorily large values

Binary search, Binary Search Now that the basic framework is working, ...

Binary Search Now that the basic framework is working, it is time to begin implementing a few alternative search functions. Each of these search algorithms have strengths and

Explain how server form post-back works, Briefly explain how server form po...

Briefly explain how server form post-back works?  Post Back: The process in which a Web page sends data back to the similar page on the server. View State: View State is the m

Name the popular security measures, Name the popular security measures ...

Name the popular security measures A number of security products covering a broad range of methods are available in the market. Most popular of all the security measures are th

How do subroutines help in program writing, How do subroutines help in prog...

How do subroutines help in program writing? Some of the significant characteristics of Subroutine that help in program writing are: A subroutine is named, each have a

Interconnection network in the form of a linear array, Q. Interconnection n...

Q. Interconnection network in the form of a Linear Array? The sorting problem particularly selected is bubble sort and interconnection network may be represented as n processor

Over fitting considerations, Over fitting Considerations : Hence in le...

Over fitting Considerations : Hence in left unchecked there backpropagation in multi-layer networks can be highly susceptible to overfitting itself to the training examples. B

Diffrentiate b/w shared memory and distributed memory, Shared Memory  ...

Shared Memory  Shared Memory refers to memory component of a computer system in which the memory can accessed directly by any of the processors in the system. Distributed

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