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CMPT 300: Operating Systems
Review
THIS REIVEW SHOULD NOT BE USED
AS PREDICTORS OF THE ACTUAL
QUESTIONS APPEARING ON THE
FINAL EXAM.
What Will Be in The Final Exam?
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Concepts & Definitions
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Conditions & Assumptions
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E.g., interrupt, page fault
Algorithms
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E.g., contiguous allocation Vs. linked list
Events
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E.g., conditions of deadlocks?
Pros & Cons
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E.g., working set, aging
E.g., Peterson’s solution, scheduling algorithms
Data structures
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E.g., page table, process table
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How to Go Over the Materials?
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Read text book and lecture notes
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Reading lecture notes only may not be
enough
Understand the concepts and definitions
Keep thinking
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Relation between concepts
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E.g., DMA Vs. paging
Why does an algorithm work here?
Extensions and implications of principles
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E.g., strict alternation, Peterson’s solution
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Ch01: Overview of OS
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OS structures
Hardware
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Basic concepts
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CPU, memory, disk, bus, DMA
Process (thread), deadlock, I/O, file system
Sections not covered in the final exam
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1.2. History of operating systems
1.3. The operating system zoo
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Ch02: Processes And Threads
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Processes
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Differences with programs?
States and transitions
Process table
Fork()
Threads
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Differences with processes? Pros & Cons?
Kernel space Vs. user space implementation
Typical applications ( I/O and CPU mixed
task)
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Ch02 (Cont.)
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Inter-process communication
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Race condition
Critical region & Mutual exclusion
Busy waiting
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Disable interrupts, lock variables, strict alternation,
Peterson’s solution
Sleep & wakeup calls, mutexes, semaphores,
monitors, message passing
Classical IPC problems
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How to apply mechanisms to solve problems?
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Ch02 (Cont.)
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Scheduling
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Preemptive Vs. non-preemptive
Benchmarks: turnaround time, throughput,
response time
FCFS, SJF, RR, MQ, etc
Three-level scheduling
Sections not covered in exam
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2.5.4: real-time scheduling
2.5.5 policy Vs. mechanism
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Ch03: Deadlocks
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Conditions for deadlock
Solutions for deadlock problem
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Ostrich algorithm
Detection and recovery
Avoidance
Prevention
Other issues
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Two-phase locking
Starvation
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Ch04: Memory Management
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Basic management
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Swapping
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Fixed partitions (single queue Vs. multiple queues)
Degree of multi-programming
Relocation and protection (base & limit registers)
Bitmaps Vs. linked list
Scenario: memory not enough
External fragmentation (memory compaction)
Virtual memory
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Paging: pages Vs. page frames, page faults
MMU, TLB, page table, page table entry
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Ch04 (Cont.)
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Page replacement algorithms
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Modeling
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NRU, FIFO, second chance, clock, LRU, NFU, aging
Working set, WSClock algorithm
Assumptions, relations
Belady’s anomaly
Stack algorithm
Design issues
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Global Vs. local, page sizes, shared pages, copyon-write
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Ch04 (Cont.)
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Implementation
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Segmentation
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Page fault handling, backing stores
Advantages
Pure segmentation Vs. segmentation with
paging
Sections not covered in final exam
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4.6.7, 4.7.3, 4.7.6, 4.8.3
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Ch05: I/O
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Principles of I/O hardware
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Principles of I/O software
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Device controllers
Memory-mapped I/O Vs. I/O port number
DMA Vs. Interrupt
Goals
Three approaches
I/O software layers
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Four layers
Functions and relationship
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Ch05 (Cont.)
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Disks
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Clocks
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Structure, format, layout
Disk arm scheduling algorithms
RAID
Stable storage
Basic work principle
Sections not covered in the final exam
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In 5.4, CD-ROM, CD-R, DVD, 5.4.4
5.5.2, 5.5.3, 5.6-5.9
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Ch06: File Systems
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Files
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Attributes, operations
Memory-mapped files
Directories
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Hierarchical directory
Path name
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Ch06 (Cont.)
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Implementations
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Files: contiguous Vs. linked list, i-nodes
Directories: directory entry, long file name
Shared files
Disk space management
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Free list Vs. bitmap
Reliability
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Backup: full dump Vs. incremental dump
Consistency check: block Vs. directory
check
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Ch06 (Cont.)
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Performance
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Caching, block read ahead, reducing disk
arm motion
Sections not covered in final exam
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6.3.8: log-structured file systems
6.4.1-6.4.4
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