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

Computer organisation, How many 32K X 1 RAM chips are needed to provide a m...

How many 32K X 1 RAM chips are needed to provide a memory capacity 256 kilobytes?

#title., REPRESENTATION OF POYNOMIAL OF 2 OR MORE VARIABLES USING ARRAY

REPRESENTATION OF POYNOMIAL OF 2 OR MORE VARIABLES USING ARRAY

Programming a 64-bit processor, You are to write a C program called big_mul...

You are to write a C program called big_mult.c that multiplies two unsigned 64-bit integers, x and y, read from the command line. The output is a pair of unsigned 64-bit integers r

How future environment changes can be predicted - simulation, How future cl...

How future climate/environment changes can be predicted -  Information over time is fed into a weather/climate model -  based on changes in weather patterns, carries out a s

Java, what is java?

what is java?

What is .net and .net framework, What is .NET / .NET Framework?  It i...

What is .NET / .NET Framework?  It is a Framework in which Windows applications might be developed and run. The Microsoft .NET Framework is a platform for building, deploying,

Design a 4 to 1 multiplexer, Design a 4 to 1 Multiplexer by using the three...

Design a 4 to 1 Multiplexer by using the three variable function given by F(A, B, C) = ∑ m(1,3,5,6) Ans. The given function F(A,B,C) = ∑ m(1,3,5,6) can be implemented along wit

Explain about karnaugh maps, Q. Explain about Karnaugh Maps? Karnaugh m...

Q. Explain about Karnaugh Maps? Karnaugh maps are a suitable way of expressing and simplifying Boolean function of 2 to 6 variables. The stepwise process for Karnaugh map is.

State the number of definitions of firewall, State the number of definition...

State the number of definitions of firewall Though there exist a number of definitions of firewall, in simplest terms it can be defined as "a mechanism used to protect a truste

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