1. Operating Systems Final Exam Review

2. Topics Paging Virtual Memory File Systems I/O Devices Project 3: Macro Shell

3. Fill in the Page Table Page 0Page 1Page 2Page 3 0 1 2 3 Page Table Logical Memory Page 1Page 3 Physical Memory Page 0Page 2 0 1 2 3 4 5 6 7

4. Fill in the Page Table: Answer Page 0Page 1Page 2Page 3 1 437 0 1 2 3 Page Table Logical Memory Page 1Page 3 Physical Memory Page 0Page 2 0 1 2 3 4 5 6 7

5. Draw Arrows Page 0 Page 1 Page 2 Page 3 01 110010 00 01 10 11 Page Table Logical Memory 000 001 010 011 100 101 110 111 Physical Memory 000 001 010 011 100 101 110 111 001011 Page Offset Frame

6. Draw Arrows: Answer Page 0 Page 1 Page 2 Page 3 01 110010 00 01 10 11 Page Table Logical Memory 000 001 010 011 100 101 110 111 Physical Memory 000 001 010 011 100 101 110 111 001011 Page Offset Frame

7. Virtual Memory Page faults –What is a page fault? –What happens during a page fault? Page replacement algorithms –What is Belady’s anomaly? –How does the OPT algorithm work? –How does LRU work? –What are some LRU approximations?

8. Virtual Memory Thrashing –What is thrashing? –What is a working set? Paging tradeoffs –How does the page size affect performance?

9. File Systems Concepts –What is the file system abstraction (user view)? Implementation –Files + What is some of the info required to store a file? + What is an I-node? An linked-list w/index (FAT)? –Directories + How are directories stored? + What information does a directory have?

10. File Systems Storing files (aliases) –What is a soft-link? A hard-link? Difference? Disk management –How do you keep track of free blocks? –What do you do with bad blocks? –What is a partition?

11. I/O Devices Hardware –What is DMA? –What are some IO device types? Software –What is an interrupt handler? –How does it work?

12. I/O Devices Disks –What is the performance based on? –What is the “Elevator” algorithm? Clocks –How does a clock work?

13. Project 3: Macro Shell Sockets –What is a socket? Connection setup –How do you connect? Send and receive –How do send and receive interact?

14. Project 3: Macro Shell Server –What does the socket code look like? –What is a concurrent server? (Project 4) –What is a non-concurrent server? (Project 3) –What possible errors might the server see? Client –What does the socket code look like? –What possible errors might the client see?