CS609: System Programming Assignment No. 06 Semester: Fall 2012 Due Date: 06/02/2013

[Rania Puri]

Assalam-o-Alaikum

Assignment # 6 CS609 has been uploaded. Its due date is 06 -02- 2013. Please discuss here about the assignment

Thanks 

Instructions

Please read the following instructions carefully before submitting assignment:

It should be clear that your assignment will not get any credit if:

• The assignment is submitted after due date.
• The submitted assignment does not open or file is corrupt.
• Solution is copied from any other source.

 

Objective

The objective of this assignment is to enhance your knowledge about;

• File System
• Block size
• Internal Fragmentation

 

Assignment          

 

Part a)

10 Marks

 

What advantage and disadvantage do we get if Bytes per Sector used in a file system is too small/large? Your answer shall be in the following tabular format.

Scenario	Advantage	Disadvantage
No. of Bytes per Sector is Small
No. of Bytes per Sector is Large

 

Part b)

10 Marks

Let suppose we have to store files on a hard disk having sizes given as below.

840 Bytes, 1790 Bytes, 650 Bytes, 2470 Bytes and 2840 Bytes.

 

You have to choose an optimal size of sector on your disk which also referred as Bytes per Sector or Block Size. You have the choice to choose the Sector size only from typical values 512 Bytes, 1024 Bytes or 2048 Bytes. Do not make random guess, do some calculations and report them in your solution. Based on your calculations, answer the following questions with reasons stated briefly.

 

Question No.1: What Block size will you choose if the objective is to have optimal disk space utilization?

 

Question No.2: What Block size will you choose if the objective is to have reduced access time?

 

 

Submission

You are required to submit a single MS word file through LMS.

 

Fall%202012_CS609_6%20%281%29.doc

[Rai Wasaq]

thnxxxxxx alottt.....may ALLAH FULFIL all ur wishes......... and give u success in every field of life... ameeeeeeeeeeeen

[╰☆True☆╮]

gopan bhai cheetay o tusi..... 

cha gay o wai cha gay 

[Muhammad Safdar]

Thanks alot Ansar

[Sadan]

Thanks Hammad and Ansar

My suggestion for Ansar ONLY  : please  see answer of your  Part a.   

Scenario	Advantage	Disadvantage
No. of Bytes per Sector is Small	Increased access time i.e. decreased performance	Optimal disk utilization
No. of Bytes per Sector is Large	Reduced access time i.e. increased performance	Disk space is wasted

My observation is Decreased Performace is Disadvantage  , so it should come in Disadvantage Colmn. 

Optimal disk utilization  is advantage  

Thanks  for helping us,  but  this is what I considered  ,  may be wrong : I do not challenge,  just give it second thought.

Regards. 

[Hammad]

Yes this is correct too...He has demonstrated it with total space used rather than unused space. Both approaches are correct. This one is simpler. 

[+ M.Tariq Malik]

cs609: 6th assignment idea solution

Idea solution

Part (a)
Small:
Advantage:
Low fragmentation
Increase storage capacity
Better performance
Disadvantage:
Slower acces time
poor error correction
low reliability
Large:
Advantages:
Faster access 
Better error handling
suitable for modern systems
Disadvantages:
Fragmentation
Low capcaity
Reduced performance


Part (b)
Q1:
512 bytes block size is best because in that memory loss is least. You can use following formula to calculate memory unused space:
Unused space=Block Size-File Size
Afer putting the values in question i.e 1790, 650 etc one by on and then totaling tem for each case you will come to know that in case of 512 unused space is least so 512 byte size is best for optimum space utilization.
Question 2: 
In this case 2048 byte size is best because it will inlvolve least number of acesses and hence fastest. 

Acsesses in 2048=7
Accesses in 1024=10
Accesses in 512=19
So 2048 is best as it involves least number of accesess. 

[Adnan]

Than U So Much

Good Night

[Muhammad Ahsan Javaid Randhawa]

Please Everyone delete your own posted solution.