1. Synchronization Memory Management
Operating Systems
Synchronization
Memory Management
1) These notes are © Aiman Hanna. All copyrights reserved. For more information please to:
2) These notes are also based on: Operating Systems, 3rd edition by Garry Nutts, published by Addison Wesley, ISBN-10: | ISBN-13: These notes still totally enforce all copyrights for Nutts/ Addison Wesley. For more information on these rights, please refer to the original publication of the book.
3) VERY IMPORTANT: These notes are neither complete nor sufficient to study for the course. They are merely given so that you can follow the covered subjects. You should NEVER depend solely on these notes for your study.
Any use of these notes that results in violation of any of the copyrights indicated above is strictly prohibited.
© Dr. Aiman Hanna
Department of Computer Science Concordia University Montreal, Canada
Data Communications & Computer Networking, by: Aiman Hanna

2. Synchronization Issues
Solutions of synchronization problems should consider:
Mutual Exclusion
Good progress/no starvation
Deadlock-free

3. The Two-task Solution
Solutions to synchronization problems between two, and only two, processes
Different solutions were discusses, which illustrated how solutions may, or may not achieve:
Mutual Exclusion
Good Progress/no starvation
Deadlock-free

4. Memory Management
Different kinds of memory have different speed, capacity and price
Executables must be loaded in main for CPU to process them
Hence, limitation of main memory represent a great concern

5. Address Binding Static address binding
Utilize loader to bind addresses
Serious problems with this approach

6. Address Space What is it?
Relation between address space and main memory

7. Structure of Memory layout of Processes
Different segments of a process
What happens when the process require dynamic allocation of extra memory

8. Memory Allocation Fixed-partition memory allocation
Internal fragmentation problem
Variable-partition memory allocation
External fragmentation problems

9. Compaction
Compaction can be used to reduce external fragmentation, however
What about address binding when compaction occurs
The need of a better way to bind addresses

10. Dynamic Address Binding
Dynamic address relocation through the use of the virtual addresses idea

11. Large Processes
How large-size processes can run on small main memories
Possible breakage of process into segments and the use of swapping

12. Where is this week coverage in the textbook?
The two task solution is to be retrieved from the website
Chapter 11:
Section 11.1 to 11.4, with the following exceptions:
Skip: Figures 11.7, 11.8, 11.9 & (page 423 to 426)
Note: Figure (page 435) and its discussion will be covered in week 8