CS604GDB opening date 6 feb and closing date 7th feb

[ayesha]

Graded Discussion board

 

GDB of CS604 will be conducted on Thursday, 07 February, 2019. It will remain open for two days.

 

GDB Topic

Consider a situation in which system is using demand paging technique to load pages from Swap Space to Main Memory. Let’s suppose that a process needs to be loaded in Main Memory. Initially, there are no pages of that process in Main Memory and no free frames are available in main memory.

In that situation, which technique will be used so that process can be loaded in the main memory without affecting the degree of multi-programming and either the page fault rate will increase or decrease thereby increasing or decreasing the performance of system?  

You are required to give your own opinion. Keep your answer precise and to the point and should not exceed 6 to 8 lines.

[Asim Faiz]

Here is in written form.

Basic Page Replacement The previously discussed page-fault processing assumed that there would be free frames available on the free-frame list. Now the page-fault handling must be modified to free up a frame if necessary, as follows: 1. Find the location of the desired page on the disk, either in swap space or in the file system. 2. Find a free frame:  If there is a free frame, use it.  If there is no free frame, use a page-replacement algorithm to select an existing frame to be replaced, known as the victim frame.  Write the victim frame to disk. Change all related page tables to indicate that this page is no longer in memory. 3. Read in the desired page and store it in the frame. Adjust all related page and frame tables to indicate the change. 4. Restart the process that was waiting for this page.

[Mani Siddiqui BS VII]

CS604 GDB Idea

Basic Page Replacement
The previously discussed page-fault processing assumed that there would be free frames available on the free-frame list. Now the page-fault handling must be modified to free up a frame if necessary, as follows:

1) Find the location of the desired page on the disk, either in swap space or in the file system.
2) Find a free frame:
A. If there is a free frame, use it.
B. If there is no free frame, use a page-replacement algorithm to select an existing frame to be replaced, known as the victim frame.
C. Write the victim frame to disk. Change all related page tables to indicate that this page is no longer in memory.
3) Read in the desired page and store it in the frame. Adjust all related page and frame tables to indicate the change.
4) Restart the process that was waiting for this page.

[M AKRAM SHAKIR]

not appropriate solution

[Sam Chaudhry]

ap koe idea dy plz

[+!!++ ZIA ASAD (BSCS-7) +++++]

page fault rate will increase and performance will decrease