240-323 OS,2000

1

240-323, Part II Process Synchronization

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240-323 OS,2000

2

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Thread

240-323 OS,2000

3

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Consumer - Producer : Share Memory

240-323 OS,2000

4

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Problem with Share memory solution

240-323 OS,2000

5

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Definition Term

240-323 OS,2000

6

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Critical-Section Problem

240-323 OS,2000

7

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Critical-Section Problem (Algorithm 1)

240-323 OS,2000

8

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Critical-Section Problem (Algorithm 2)

240-323 OS,2000

9

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Critical-Section Problem (Algorithm 3)

240-323 OS,2000

10

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Critical-Section (Many Processes)

240-323 OS,2000

11

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Bakery Algorithm : Explained

240-323 OS,2000

12

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Synchronize Hardware

240-323 OS,2000

13

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Test and Set for Mutual Exclusion

240-323 OS,2000

14

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Semaphores

240-323 OS,2000

15

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Using Semaphores

240-323 OS,2000

16

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Implement Semaphores

240-323 OS,2000

17

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Implementing Semaphores

240-323 OS,2000

18

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Dead locks and Starvation

P0 P1 wait(S); wait(Q); wait(Q); wait(S);

. .

. .

. . Signal(S); Signal(Q); Signal(Q); Signal(S) ;

240-323 OS,2000

19

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Binary Semaphores

• a semaphore with an integer value that can range only between 0 and 1.• Can be simpler to implement

Wait : wait(S1);C := C -1;if C < 0 then

signal(S1);wait(S2);

endsignal(S1);

Signal : wait(S1);C := C +1;if C =< 0 then

signal(S2);else

wait(S1);

240-323 OS,2000

20

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Readers/Writers Problem

240-323 OS,2000

21

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Readers have Priority

240-323 OS,2000

22

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Comment on Reader Priority

240-323 OS,2000

23

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Writer have Priority

240-323 OS,2000

24

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Note on Writer have Priority

240-323 OS,2000

25

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Dining-Philosophers Problem