Review Guide for Test 2

Midterm Exam #2 will be Monday, November 19th.  The test is closed book, but you will be allowed one 8 1/2" x 11" sheet of paper filled with notes of your choosing. (You may write on both the front and back side of the paper.)  The exam will cover the following:

Chapter 9. Memory Management

• Paging:
• logical to physical address translation
• page-table entries
• TLB
• protection
• multilevel paging
• inverted page table
• shared pages
• Segmentation:
• logical to physical address translation
• protection
• sharing
• Segmentation with paging

 

Chapter 10. Virtual Memory (through 10.5)

• demand paging
• page fault
• page fault trap
• Architectural Problems with Paging
• Performance of Demand Paging - effective memory-access time
• locality of reference
• thrashing
• frame-allocation algorithm
• page-replacement algorithms:
  • FIFO (Belady's anomally)
  • Optimal page replacement
  • LRU
• Approximate Implementations of LRU Algorithm: Counter/History Bits, Second-Chance/Clock Replacement, and Not Recently Used (NRU) / Enchanced Second-Chance algorithm
• Frame-Allocation Algorithms
• Allocation Policies: local page replacement and global-page replacement
• Implementations of global-page replacement: Page-Fault Frequency and Working-Set

Chapter 11 - File-Systems (Through 11.8 inclusive excluding 11.1.5 and 6)

• Components: partitions, directory structure, files
• File Attributes: Symbolic Name, type, location, size, protection, time, date of access and modification, user identification
• File Operations - create, write, read, seek, delete, truncate (clear)
• Sequence of File Usage: Open, Read/Write file, Close
• Implementation data structures: per-process tables and system-wide open-file table
• File structure and Types
• Access Methods: Sequential Access, Direct Access, indexed
• Directory Operations - search for file, create file, delete file, list directory, rename file, traverse file structure (visit every file)
• Logical Directory Structure: single-level directory, two-level directory, tree-structured directory, acyclic graph directory
• Protection - control who accesses the file and for what type of usage
  • Access types - read, write, execute, append, delete, list name and attribute
  • Access List and Groups
  • Unix approach - rwx bits
• Characteristics of Disk

1) Random Access by moving R/W heads, waiting for rotation

2) Blocks can be rewritten in place

• File-System Organization - layered design
• Allocation Methods: Contiguous, Linked, FAT (File Allocation Table), Indexed
• Handling Large Indexes: Linked list of Index Blocks, Multilevel index, Combined Scheme - BSD Unix inode
• Free-space Management:
• free-space list implementations: Bit Vector, Linked List, Grouping, Counting

Chapter 12. I/O Systems (through 12.3 inclusive)

Goal: To make the I/O subsystem independent of the I/O hardware.

• Major Acess Conventions: Block I/O, Character-stream I/O, Memory-mapped File Access, Network Devices, Clocks and Timers
• Blocking vs. Nonblocking I/O
• Blocking I/O system calls , Nonblocking I/O system , Asynchronous I/O system calls
• Ways to check on the progress of the I/O: polling, I/O multiplexing, Signal-Driven I/O

Chapter 13. Mass-Storage Structure

• Disk Scheduling: FCFS, SSTF, SCAN, C-SCAN, LOOK, C-LOOK
• Disk Management: formatting, boot block, bad blocks
• Swap-space management: swap-space use and location

Study Hints

For the previous exam I gave you a "sample exam."  I did this mostly just to make you familiar with the structure of the exam I might give.  For this exam I am not making a formal sample exam.  I don't feel too bad about this for two reasons

1. You know what my test should look like
2. If I were to write a sample exam, it would look nearly identical to the homework assignment that you are working on at the moment.

My study hints to you.

1. Go through the homework questions well.  It is likely that roughly 1/2 the questions I ask will be simple modifications of these questions.
2. Play the "second guess Dr. Schafer" game.  What might I do to get the other 1/2 of the questions?  Take a bit to browse the questions that I DIDN'T ask you to answer for HW#2.  Which of these questions might make good test questions AS IS?  Which of these might make good test questions with only minor modifications?  Remember that I like to ask vocab questions that ask you to explain the difference between a pair of "related" vocab terms.  What terms in the book might make good pairs for this kind of question?