CS439: Principles of Computer Systems

Discussion Section 5 Problem Set

Due in Section on Friday, March 1, 2023

The problem set must be completed before section and brought to section. To ensure that your problem set is turned in correctly and that you receive credit for discussion section, you must follow these guidelines exactly.

Include the following header at the top of your file:

Discussion Section Problem Set #: 
Student Name:
EID:
If I could ride on the back of an animal it would be:


Partner Name:
EID:
If I could ride on the back of an animal it would be:

You may either type your answers or write them by hand, but you must have a copy with you in discussion section.

In discussion section, your TA will check that you worked with your partner, you made a good effort on the problem set, you are participating in the discussions in section, and you are ready and able to answer when called upon. If all of those are true, you will receive credit for discussion section that day. Note that a "good effort" on the problem set includes that all answers are in words unique to you and your partner and not copied from anywhere else, including the slide deck.

What are overlays? How and why were they created?
What causes a memory exception? What is the end result for the running process?
Compare and contrast static and dynamic relocation. When and how is address translation performed in each case? Name one advantage and disadvantage of each.
Name two advantages of paging over relocation.
What is a virtual address? What is a physical address? How do they relate to each other?
Sam P. Hacker is a Head Guru in a software company known for operating systems with very sorry quality. Hacker suggested a trick to reduce the pressure on the swap space. Instead of swapping out pages that belong to code texts into the swap area, the operating system could just take away the memory frames. If the code page is needed later, it could be paged directly from its binary file. Hacker's argument is that the operating system will save time by not storing the code page into the swap space, and will save space in the swap area. The code text exists on disk anyway, and could be fetched from there. Would you approve of this design? Why or why not?