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

Determine the uses of defparam, Using defparam Parameter values can be ...

Using defparam Parameter values can be changed in any module instance in the design with keyword defparam. Hierarchical name of the module instance can be used to override para

what is a real time system, A real time system is a computer system that u...

A real time system is a computer system that updates the information at the similar rate it receives it. Real time system is of two types:- a)  Hard real time system and

How does tcp achieve reliability, How does TCP achieve reliability? One...

How does TCP achieve reliability? One of the most significant technologies is retransmission. While TCP stands data the sender compensates for packet loss through implementing

Inspirations of artificial intelligence, Inspirations of artificial intelli...

Inspirations of artificial intelligence: Artificial Intelligence research can be easily understood by following example in terms of how the following question has been answere

Explain about mainframes computer, Q. Explain about Mainframes computer? ...

Q. Explain about Mainframes computer? Mainframes, capable of executing in excess of 53 MIPS, are high-performance, general- purpose computers supporting very large databases, r

C programming, At a shop of marbles, packs of marbles are prepared. Packets...

At a shop of marbles, packs of marbles are prepared. Packets are named A, B, C, D, E …….. All packets are kept in a VERTICAL SHELF in random order. Any numbers of packets with thes

What is an arithmetic processor, Q. What is an arithmetic processor? A ...

Q. What is an arithmetic processor? A distinctive CPU necessitates most of the control and data processing hardware for implementing non-arithmetic functions. As the hardware c

Breif on loosely coupled systems, Loosely Coupled Systems These s...

Loosely Coupled Systems These systems don't share global memory since shared memory concept increases the problem of memory conflicts, which consecutively slows down the

What is a turing machine, What is a Turing Machine?  Turing machine is...

What is a Turing Machine?  Turing machine is a simple mathematical model of a computer. TM has unlimited an unrestricted memory and is a much more accurate model of a general

Cg transformations, magnify a triangle a(0,0), b(1,1), c(5,2) twice its siz...

magnify a triangle a(0,0), b(1,1), c(5,2) twice its size hile keeping c as fix

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