CS501 Assignment No.4 Discussion Due Date 25-06-2012

[matloob Hussain]

Q1 Marks = 15

Assume that three I/O devices are connected to a 16-bit, 100 MIPS CPU. The first device is a hard drive with a maximum transfer rate of 2MB/sec. It has a half word (16-bit) bus. The second device is a floppy drive with a transfer rate of 10KB/sec over 8-bit bus, and the third device is a keyboard that must be polled 25 times per second. Assuming that the polling operation requires 40 instructions for each I/O device, determine the percentage of CPU time required to poll each device and also state what you infer after calculating these percentages.

[Osama Ali]

Hmmmm....

[matloob Hussain]

[akram ul haq]

Book me se ha example but values change hain kuch samaj ni lagi....................

any one.............................have idea.

[nazma ashraf]

buk mein pg#311 py example hai.........wahan 10x10^6 hai hm ny 100x10^6 laina hai wahan 20 instruction for each device hai hm ny 40 laina hai........baqi exact calculations ki mjhy smjh nai aa rhi koi hai yahan jo discuss kry bcz agr  aj he assignmnt ho jaye to acha hai

[matloob Hussain]

Example mn 32-bit hy jb k is question mn 16-bit hy

[mohammadusman]

dear u have to consult book for this assignment there is no issue if u read some pages of topic related to book example on page no. 311.

[nazma ashraf]

jis ksi ny b assignmnt kr le ho kya wo answrz share kr skta hai plzzzzzzzz confirmation k liye

[Roshi]

There are some confusion in solving question due to diffrent values so if each of one should share the answers so that everyone should do the correct solution.

Thanks

[Dua Zahra]

The percentage of CPU time required for polling of hard drive is 10.24%, for floppy drive: 0.1024% and for keyboard is 0.001%.

i want to know that what is meant by: " also state what you infer after calculating these percentages?"

[zain ul abdeen]

Dua sis

is main inferka mutlab hy kay ka app kay pass jo persent age aye hy us kay mutabak ye tamam devices kam kar sakti hy kay nahi agr karsakti hy to theek warna app kah sakty ho ky ye devices is kay sath kam nahi kar sakti

[Muhammad Imran]

As i think the calculation will be as follow :-

 500 x 2^10 x40 = 20480000

percentage of CPU time required for polling is

(2.04 x 10^6) / (100 x10^6) = 20.4%

???

 

 

 

 

[Muhammad Imran]

how 0.1024  ???/