Operating System question please

kb100 · 08-28-2006, 04:55 AM

Hi there. Was wondering if anyone knew how to calculate this:

“The XYZ operating system uses both segmentation and demand-paged virtual memory. It supports up to 256 segments per process. Each segment uses a 24-bit virtual address with 4096-byte page frames. The page replacement strategy is NRU (not recently used). The paging store may be a single file on a user volume, or distributed across several files on one or more volumes.”

a) Calculate the maximum number of pages available to a process in this operating system.

thanks

Mega Man X · 08-28-2006, 05:06 AM

Quote:

Originally Posted by kb100

Hi there. Was wondering if anyone knew how to calculate this:

“The XYZ operating system uses both segmentation and demand-paged virtual memory. It supports up to 256 segments per process. Each segment uses a 24-bit virtual address with 4096-byte page frames. The page replacement strategy is NRU (not recently used). The paging store may be a single file on a user volume, or distributed across several files on one or more volumes.”

a) Calculate the maximum number of pages available to a process in this operating system.

thanks

I think that according to our rules, we are not supposed to answer questions regarding your homework:

Quote:

Do not expect LQ members to do your homework - you will learn much more by doing it yourself.

Very good advice indeed...

kb100 · 08-28-2006, 05:13 AM

Well actually this isnt homework. Im going through a past paper and i really havent learnt how to do this at all. Can you still not explain the answer to me?

Mega Man X · 08-28-2006, 05:49 AM

I see. I think it is fine then

. Unfortunatelly, I don't know the answer. That is way out of my league. I can help you creating a pong game in Java though... ^^

kb100 · 08-28-2006, 06:01 AM

I am currently doing a past paper on Operating Systems and have a few questions which i really do not understand how i could get the answer. Could someone explain an answer to me please?

thanks

Code:

“The XYZ operating system uses both segmentation and demand-paged virtual memory. It supports up to 256 segments per process. Each segment uses a 24-bit virtual address with 4096-byte page frames. The page replacement strategy is NRU (not recently used). The paging store may be a single file on a user volume, or distributed across several files on one or more volumes.”

a) Calculate the maximum number of pages available to a process in this operating system.

Code:

A disk has 200 tracks and the request queue for tracks contains, in the order received, 55, 58, 39, 18, 90, 160.  Assuming that the disk arm is initially at track 100 and that no more requests arrive until all entries in the queue have been serviced then determine the average seek time for the disk-scheduling algorithms known as SSTF and SCAN (elevator).  For each algorithm identify one weakness of that algorithm.

Code:

RAID systems are now commonly used to provide reliability, efficiency and fault tolerance.  The following schematic diagram is typical of what is known as RAID-3.  Discuss the advantages and disadvantages of such a configuration and suggest one way in which it could be improved.  						  [4 marks]
1		2		3		1 XOR 2 XOR 3
4		5		6		4 XOR 5 XOR 6
7		8		9		7 XOR 8 XOR 9
…		…		…		…

thanks

sundialsvcs · 08-28-2006, 01:08 PM

This is homework. Please don't insult any of us by suggesting that it is anything else, because not only have all of us answered such drivel, some of us have actually assigned it.

The purpose of all this is: find the answer yourself. That's what you, and/or your parents, are supposedly "paying the big bucks for."

aysiu · 08-28-2006, 02:05 PM

I really hope no one falls for this "past homework" BS. Can we lock this thread?

XavierP · 08-28-2006, 05:41 PM

There is no reason that he can't be provided with help without giving the answer. If anyone can point the OP to a relevant webpage or a text which will clearly explain how to get the answer and what it is asking, that will help much more than simply giving the answer.

That way, if it is a past paper, we're helping out with that and with the OP's general knowledge on the subject and if it is current homework....well, see the start of this sentence

XavierP · 08-28-2006, 05:41 PM

Quote:

Originally Posted by aysiu

I really hope no one falls for this "past homework" BS. Can we lock this thread?

Oh, and the "report" button works much better for this sort of thing than a post does. Just saying