Operating Systems, Fall 2007, Homework 6
This homework will be covered in practise session on Thursday 11.10.2006 (week 41).
The exercises are based on chapter 8.
- Memory Managent Policies
- Problem 8.4 from course book [Stal05] (Problem 8.2. [Stal01]. Please notice that the problem has slightly changed: The second row in the R bit column should be 1. The whole R bit column is 0 1 1 1.)
- Replacement algorithm
- Problem 8.5 from text book [Stal05, s. 384] (Probl. 8.3 [Stal01])
- What is special with this situation? What can you deduce from it?
- Working Set
- Problem 8.15 a) from course book [Stal05]: (The problem is not available in the 4th edition.)
Consider the following sequence of page references (each element in the sequence represents a page number):
1 2 3 4 5 2 1 3 3 2 3 4 5 4 5 1 1 3 2 5
Draw a diagram similar to that of Figure 8.19 for the reference sequence just defined for the values (delta)= 1,2,3,4,5,6. - How does the working set size vary during the execution? If you should decide a fixed maximum number of page frames allocated to this process, what size would you choose and why?
- Problem 8.15 a) from course book [Stal05]: (The problem is not available in the 4th edition.)
- VSWS
- Problem 8.16 from text book [Stal05] (Probl. 8.13 [Stal01])
- What if Q was global, but dynamic. Give a similar mechanism for this
case. Compare it to the mechanism given in (a). When would it be better?
When worse?
- Linux.
Linux memory management maps a continuous virtual memory area into a continuous block of physical frames.- What is the gain with this approach?
- What problems does it cause?
The exam covers
- exercises 1-6 and
- book chapters 1-8 (sections 5.1 - 6.6 are not included).
- Please notice that the second team task is part of this exam, even if it's deadline is after the exam.
You also need to take pencils (or pens) with you to the exam. You may also take some snacks.
You are not allowed to have any notes, books or other written material available in the exam.