CS414, Fall 2005

Homework 7

Posted 11/1/05

There may be a pop-quiz on these homework questions during class
on Nov. 8.  (Note that the 2nd prelim is Nov 10).

You may work together on these homework questions.  However, I strongly advise
you to try to solve them yourself first, then check your answers with the
solution set afterwards (at least for the first 8 questions).   Please do
not discuss the homework on the class discussion mailing list.
which is posted on CMS).  

 
1. p408 Exercise 10.2

2. p408 Exercise 10.7

3. p409 Exercise 10.10

4. p447 Exercise 11.1

5. p448 Exercise 11.4

6. p448 Exercise 11.5

7. p448 Exercise 11.9	

8. p448 Exercise 11.10

9. If a free-space list is completely lost due to a crash, is there any way
   to recover it? 

10. In some systems, the i-nodes are kept at the start of the disk. An
    alternative design is to allocate an i-node when a file is created and put
    the i-node at the start of the first block of the file. Discuss the pros
    and cons of this alternative.

11. Assuming the style of i-node storage where the i-node is stored at the
    first block of a file, how many disk operations are needed to fetch
    the i-node for the file /a/b/c/d/e (where a/b/c/d is the absolute directory
    path, and 'e' is the file name)? Assume that the i-node for the root
    directory is in the memory, but nothing else along the path is in the
    memory. Also assume that each directory fits in one disk block.