Computer

For Online Computer Support, Ask a Computer Technician

Computer

# 3. Given the following characteristics for a disk pack with

Customer Question
10 platters yielding 18 recordable...
3. Given the following characteristics for a disk pack with 10 platters yielding 18 recordable surfaces: rotational speed = 10 ms transfer rate = 0.1 ms/track density per track = 19,000 bytes number of records to be stored = 200,000 records size of each record = 160 bytes block size = 10 logical records number of tracks per surface = 500

Find the following:
a. Number of blocks per track
b. Waste per track
c. Number of tracks required to store the entire file
d. Total waste to store the entire file
e. Time to write all of the blocks (Use rotational speed; ignore the time it takes to move to the next track.)
f. Time to write all of the records if they're not blocked (Use rotational speed; ignore the time it takes to move to the next track.)
g. Optimal blocking factor to minimize waste
h. What would be the answer to (e) is the time it takes to move to the next track were 5 ms?
i. What would be the answer to (f) is the time it takes to move to the next track were 5 ms?

Submitted: 7 years ago.Category: Computer
Show More
Show Less
2/16/2010
Tech Support Specialist: Molinari, Computer Support Specialist replied 7 years ago
Molinari, Computer Support Specialist
Category: Computer
Satisfied Customers: 4,459
Experience: Certified IT Guru since C-64 and Amiga, expert at grey areas....
Verified

a. Number of blocks per track:

Size of block = 10*160 bytes = 1600 bytes

1 track can hold = 19000 bytes

so no. of blocks per track will be = 19000/1600 = 11.875(approx 11)

b. Waste per track:

Data that can be stored on 1 track is = 19000 Bytes
But block size is fixed = 1600 bytes
So only 11 blocks can be saved = 1600*11 = 17600 bytes
remaining all gets wasted
so Waste per track will be = 19000 - 17600 = 1400 bytes

c. Number of tracks required to store the entire file:

Total number of records to be stored = 200000
1 record size = 160 bytes
so total required space will be = 200000*160 = 32000000 bytes

Track size is = 19000 bytes

So, No of tracks required will be = 32000000/19000 = 1684.21 (1685 approx)

d. Total waste to store the entire file:

waste per track was = 1400 bytes.
waste per 1685 track will be = 1400*1685 =(NNN) NNN-NNNNbytes

e. Time to write all of the blocks:

Total no. of blocks are = 1685 * 11 = 18535
will be written at the rate of .1ms/track
and total no of track are 1685 so time taken will be = 1685*0.1 = 168.5 ms

h.
answer will be = 1685*0.2 = 337 ms

Molinari, Computer Support Specialist
Category: Computer
Satisfied Customers: 4,459
4,459 Satisfied Customers
Experience: Certified IT Guru since C-64 and Amiga, expert at grey areas....

Molinari is online now

A new question is answered every 9 seconds

• Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
• Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

## What Customers are Saying:

My Expert answered my question promptly and he resolved the issue totally. This is a great service. I am so glad I found it I will definitely use the service again if needed.

One Happy CustomerNew York

I am very happy with my very fast response. Eric is very knowledgeable in the subject area. Thank you!

RPAustin, TX

Hi John, Thank you for your expertise and, more important, for your kindness because they make me, almost, look forward to my next computer problem. After the next problem comes, I'll be delighted to correspond again with you. I'm told that I excel at programing. But system administration has never been one of my talents. So it's great to have an expert to rely on when the computer decides to stump me. God bless, Bill

The Expert answered my Mac question and was patient. He answered in a thorough and timely manner, keeping the response on a level that could understand. Thank you!

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

< Previous | Next >

## Meet the Experts:

Andy

Computer Consultant

5,316 satisfied customers

11yr exp, Comp Engg, Internet expert, Web developer, SEO

Engineer John C.

Computer Science Engineer

3,228 satisfied customers

Computer Science Engineer with 10 years of experience in Computer Support, and Microsoft, A+ and Cisco certified

Ryan H.

Computer Support Specialist

1,741 satisfied customers

A+ Certified Technician - 10 Years experience working with all types of computer systems.

Jane Lefler

Sr Prog Analyst / Technician

2 satisfied customers

Computer Programmer / Technician/ Consultant 16+ years

Frederick S.

Computer Specialist

7,241 satisfied customers

Computer technician and founder of a home PC repair company.

lifesaver

Computer Software Engineer

4,288 satisfied customers

Engineering degree in Computer science,Microsoft Certified Professional.JA computer expert.

Sudipto

Hardware Engineer

4,167 satisfied customers

Certificate Course In Computer Maintenance

< Previous | Next >

Related Computer Questions
I can't get into my Emails-password not accepted even though
I can't get into my Emails-password ***** accepted even though I said to … read more
Kamil Anwar
IT Consultant / Systems Engineer
Bachelor\u0027s Degree
434 satisfied customers
It won't connect with the internet. I get a stop code:
It won't connect with the internet. I get a stop code: inaccessible boot device message. … read more
David L.
Bachelor\u0027s Degree
6 satisfied customers
Gateway GT5682. A little ancient......usb ports not working.
Gateway GT5682. A little ancient......usb ports not working. Keyboard is a ps/2 plug in. So keyboard works. … read more
Russell H.
computer technology consultant
781 satisfied customers
Nothing...want to cancel my SKYPE contract and phone# Have
nothing...want to cancel my SKYPE contract and phone# … read more
ChrisC
PC Technician
Associate Degree
660 satisfied customers
I purchased Office 365 yesterday from a Staples outlet but I
My name is ***** ***** I purchased Office 365 yesterday from a Staples outlet but I cant seem to get it to load. I have the 5 user edition … read more
Kamil Anwar
IT Consultant / Systems Engineer
Bachelor\u0027s Degree
434 satisfied customers
I bought Microsoft Office 365 at WalMart the same day I
I bought Microsoft Office 365 at WalMart the same day I bought a Lenovo computer. The computer has had a catastrophic failure and the only thing I have is the Product Key. What do I need to do to get … read more
Kamil Anwar
IT Consultant / Systems Engineer
Bachelor\u0027s Degree
434 satisfied customers
I have a Kodak Easyshare DX6340 that works perfectly. I
Hi! I have a Kodak Easyshare DX6340 that works perfectly. I upgraded to Windows 10 and find the camera is not compatible. Outside of getting a new camera, is there any way to make it work? Thanks! … read more
Viet - Computer Tech
Computer Technican
Bachelor\u0027s Degree
953 satisfied customers
I have the required (or newer) versions of Chrome, Firefox
I have the required (or newer) versions of Chrome, Firefox and Safari but can't stream a prime tv series … read more
Mike Taylor
40 satisfied customers
Microsoft called and said do not uses my computer,and have
Microsoft called and said do not uses my computer,and have someone look into the problem … read more
Michelle
Manager operations
Bachelor\u0027s Degree
1,275 satisfied customers
Why am I banned from my ps4. Do u need the new amex number I
why am I banned from my ps4. Do u need the new amex number I just got … read more
Mike Taylor
40 satisfied customers
My keyboard locked up. i cannot get it going again. i was
hi. my keyboard locked up. i cannot get it going again. i was stupid. i thought tweakbit was microsoft. the keyboard stopped working after i downloaded some clean up programs. … read more
Sheri
Bachelor\u0027s Degree
105 satisfied customers
I mistakenly deleted Word from my PC. I cannot restore it
I mistakenly deleted Word from my PC. I cannot restore it from the Recycle Bin. … read more
Jason Jones
AAS Information Technology
6,320 satisfied customers
How can i switch back to my old format, hp not sure on the
just tonight. it told me to click a icon at the top right but nothing happened … read more
Viet - Computer Tech
Computer Technican
Bachelor\u0027s Degree
953 satisfied customers
I have a lawyer client who has a Bluray disc / audio
I have a lawyer client who has a Bluray disc / audio interview for a trial. It will not play on his computer. Do I need to purchase a bluray player for computer? I did load VLC bluray but would not pl… read more
Michael Hannigan
Bachelor\u0027s Program
239 satisfied customers
Can't finish typing email when following message comes up on
can't finish typing email when following message comes up on screen Sorry, something unexpected happned and winfows Live Mail must close. Your most recent changes may not be saved … read more
Michelle
Manager operations
Bachelor\u0027s Degree
1,275 satisfied customers
Friday night i fell for a tech support scam from a group
friday night i fell for a tech support scam from a group called mwsupport. I gave them control of my computer for a time and they installed some icons on my desktop including ATF-Cleaner. I paid some … read more
Michelle
Manager operations
Bachelor\u0027s Degree
1,275 satisfied customers
My charity has received approval from MS for the donation of
My charity has received approval from MS for the donation of 3 Windows 10 licenses and three MS Office licenses and have paid MS for the discounted prices. In attempting to download the software, I ha… read more
Mike Taylor
40 satisfied customers
I have a new Lenovo laptop forgot the password. I cannot