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A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z as
follows. Each of the processes W and X reads x from memory, increments by one, stores it to
memory, and then terminates. Each of the processes Y and Z reads x from memory, decrements by
two, stores it to memory, and then terminates. Each process before reading x invokes the P
operation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on the
semaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximum
possible value of x after all processes complete execution?
follows. Each of the processes W and X reads x from memory, increments by one, stores it to
memory, and then terminates. Each of the processes Y and Z reads x from memory, decrements by
two, stores it to memory, and then terminates. Each process before reading x invokes the P
operation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on the
semaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximum
possible value of x after all processes complete execution?
- a)-2
- b)-1
- c)1
- d)2
Correct answer is option 'D'. Can you explain this answer?
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Given Information:
- There are four concurrent processes: W, X, Y, and Z.
- A shared variable x is initialized to zero.
- Processes W and X increment x by one and store it to memory.
- Processes Y and Z decrement x by two and store it to memory.
- Before reading x, each process invokes the P operation on a counting semaphore S.
- After storing x to memory, each process invokes the V operation on semaphore S.
- Semaphore S is initialized to two.
Analysis:
Let's analyze the execution of the processes step by step to determine the maximum possible value of x.
Process W:
1. Process W reads x from memory (value of x = 0).
2. Process W invokes the P operation on semaphore S (value of S = 2 - 1 = 1).
3. Process W increments x by one (value of x = 0 + 1 = 1).
4. Process W stores x to memory.
5. Process W invokes the V operation on semaphore S (value of S = 1 + 1 = 2).
6. Process W terminates.
Process X:
1. Process X reads x from memory (value of x = 1).
2. Process X invokes the P operation on semaphore S (value of S = 2 - 1 = 1).
3. Process X increments x by one (value of x = 1 + 1 = 2).
4. Process X stores x to memory.
5. Process X invokes the V operation on semaphore S (value of S = 1 + 1 = 2).
6. Process X terminates.
Process Y:
1. Process Y reads x from memory (value of x = 2).
2. Process Y invokes the P operation on semaphore S (value of S = 2 - 1 = 1).
3. Process Y decrements x by two (value of x = 2 - 2 = 0).
4. Process Y stores x to memory.
5. Process Y invokes the V operation on semaphore S (value of S = 1 + 1 = 2).
6. Process Y terminates.
Process Z:
1. Process Z reads x from memory (value of x = 0).
2. Process Z invokes the P operation on semaphore S (value of S = 2 - 1 = 1).
3. Process Z decrements x by two (value of x = 0 - 2 = -2).
4. Process Z stores x to memory.
5. Process Z invokes the V operation on semaphore S (value of S = 1 + 1 = 2).
6. Process Z terminates.
Final Value of x:
After all processes have completed execution, the final value of x is -2. Therefore, the maximum possible value of x is 2, which corresponds to option D.
- There are four concurrent processes: W, X, Y, and Z.
- A shared variable x is initialized to zero.
- Processes W and X increment x by one and store it to memory.
- Processes Y and Z decrement x by two and store it to memory.
- Before reading x, each process invokes the P operation on a counting semaphore S.
- After storing x to memory, each process invokes the V operation on semaphore S.
- Semaphore S is initialized to two.
Analysis:
Let's analyze the execution of the processes step by step to determine the maximum possible value of x.
Process W:
1. Process W reads x from memory (value of x = 0).
2. Process W invokes the P operation on semaphore S (value of S = 2 - 1 = 1).
3. Process W increments x by one (value of x = 0 + 1 = 1).
4. Process W stores x to memory.
5. Process W invokes the V operation on semaphore S (value of S = 1 + 1 = 2).
6. Process W terminates.
Process X:
1. Process X reads x from memory (value of x = 1).
2. Process X invokes the P operation on semaphore S (value of S = 2 - 1 = 1).
3. Process X increments x by one (value of x = 1 + 1 = 2).
4. Process X stores x to memory.
5. Process X invokes the V operation on semaphore S (value of S = 1 + 1 = 2).
6. Process X terminates.
Process Y:
1. Process Y reads x from memory (value of x = 2).
2. Process Y invokes the P operation on semaphore S (value of S = 2 - 1 = 1).
3. Process Y decrements x by two (value of x = 2 - 2 = 0).
4. Process Y stores x to memory.
5. Process Y invokes the V operation on semaphore S (value of S = 1 + 1 = 2).
6. Process Y terminates.
Process Z:
1. Process Z reads x from memory (value of x = 0).
2. Process Z invokes the P operation on semaphore S (value of S = 2 - 1 = 1).
3. Process Z decrements x by two (value of x = 0 - 2 = -2).
4. Process Z stores x to memory.
5. Process Z invokes the V operation on semaphore S (value of S = 1 + 1 = 2).
6. Process Z terminates.
Final Value of x:
After all processes have completed execution, the final value of x is -2. Therefore, the maximum possible value of x is 2, which corresponds to option D.
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A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z asfollows. Each of the processes W and X reads x from memory, increments by one, stores it tomemory, and then terminates. Each of the processes Y and Z reads x from memory, decrements bytwo, stores it to memory, and then terminates. Each process before reading x invokes the Poperation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on thesemaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximumpossible value of x after all processes complete execution?a)-2b)-1c)1d)2Correct answer is option 'D'. Can you explain this answer?
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A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z asfollows. Each of the processes W and X reads x from memory, increments by one, stores it tomemory, and then terminates. Each of the processes Y and Z reads x from memory, decrements bytwo, stores it to memory, and then terminates. Each process before reading x invokes the Poperation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on thesemaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximumpossible value of x after all processes complete execution?a)-2b)-1c)1d)2Correct answer is option 'D'. Can you explain this answer? for GATE 2024 is part of GATE preparation. The Question and answers have been prepared according to the GATE exam syllabus. Information about A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z asfollows. Each of the processes W and X reads x from memory, increments by one, stores it tomemory, and then terminates. Each of the processes Y and Z reads x from memory, decrements bytwo, stores it to memory, and then terminates. Each process before reading x invokes the Poperation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on thesemaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximumpossible value of x after all processes complete execution?a)-2b)-1c)1d)2Correct answer is option 'D'. Can you explain this answer? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z asfollows. Each of the processes W and X reads x from memory, increments by one, stores it tomemory, and then terminates. Each of the processes Y and Z reads x from memory, decrements bytwo, stores it to memory, and then terminates. Each process before reading x invokes the Poperation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on thesemaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximumpossible value of x after all processes complete execution?a)-2b)-1c)1d)2Correct answer is option 'D'. Can you explain this answer?.
A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z asfollows. Each of the processes W and X reads x from memory, increments by one, stores it tomemory, and then terminates. Each of the processes Y and Z reads x from memory, decrements bytwo, stores it to memory, and then terminates. Each process before reading x invokes the Poperation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on thesemaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximumpossible value of x after all processes complete execution?a)-2b)-1c)1d)2Correct answer is option 'D'. Can you explain this answer? for GATE 2024 is part of GATE preparation. The Question and answers have been prepared according to the GATE exam syllabus. Information about A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z asfollows. Each of the processes W and X reads x from memory, increments by one, stores it tomemory, and then terminates. Each of the processes Y and Z reads x from memory, decrements bytwo, stores it to memory, and then terminates. Each process before reading x invokes the Poperation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on thesemaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximumpossible value of x after all processes complete execution?a)-2b)-1c)1d)2Correct answer is option 'D'. Can you explain this answer? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z asfollows. Each of the processes W and X reads x from memory, increments by one, stores it tomemory, and then terminates. Each of the processes Y and Z reads x from memory, decrements bytwo, stores it to memory, and then terminates. Each process before reading x invokes the Poperation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on thesemaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximumpossible value of x after all processes complete execution?a)-2b)-1c)1d)2Correct answer is option 'D'. Can you explain this answer?.
Solutions for A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z asfollows. Each of the processes W and X reads x from memory, increments by one, stores it tomemory, and then terminates. Each of the processes Y and Z reads x from memory, decrements bytwo, stores it to memory, and then terminates. Each process before reading x invokes the Poperation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on thesemaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximumpossible value of x after all processes complete execution?a)-2b)-1c)1d)2Correct answer is option 'D'. Can you explain this answer? in English & in Hindi are available as part of our courses for GATE.
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A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z asfollows. Each of the processes W and X reads x from memory, increments by one, stores it tomemory, and then terminates. Each of the processes Y and Z reads x from memory, decrements bytwo, stores it to memory, and then terminates. Each process before reading x invokes the Poperation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on thesemaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximumpossible value of x after all processes complete execution?a)-2b)-1c)1d)2Correct answer is option 'D'. Can you explain this answer?, a detailed solution for A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z asfollows. Each of the processes W and X reads x from memory, increments by one, stores it tomemory, and then terminates. Each of the processes Y and Z reads x from memory, decrements bytwo, stores it to memory, and then terminates. Each process before reading x invokes the Poperation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on thesemaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximumpossible value of x after all processes complete execution?a)-2b)-1c)1d)2Correct answer is option 'D'. Can you explain this answer? has been provided alongside types of A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z asfollows. Each of the processes W and X reads x from memory, increments by one, stores it tomemory, and then terminates. Each of the processes Y and Z reads x from memory, decrements bytwo, stores it to memory, and then terminates. Each process before reading x invokes the Poperation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on thesemaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximumpossible value of x after all processes complete execution?a)-2b)-1c)1d)2Correct answer is option 'D'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice A shared variable x, initialized to zero, is operated on by four concurrent processes W, X, Y, Z asfollows. Each of the processes W and X reads x from memory, increments by one, stores it tomemory, and then terminates. Each of the processes Y and Z reads x from memory, decrements bytwo, stores it to memory, and then terminates. Each process before reading x invokes the Poperation (i.e., wait) on a counting semaphore S and invokes the V operation (i.e., signal) on thesemaphore S after storing x to memory. Semaphore S is initialized to two. What is the maximumpossible value of x after all processes complete execution?a)-2b)-1c)1d)2Correct answer is option 'D'. Can you explain this answer? tests, examples and also practice GATE tests.
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