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Three concurrent processes X, Y, and Z execute three different code segments that access and
update certain shared variables. Process X executes the P operation (i.e., wait) on semaphores
a, b and c; process Y executes the P operation on semaphores b, c and d; process Z executes
the P operation on semaphores c, d, and a before entering the respective code segments. After
completing the execution of its code segment, each process invokes the V operation (i.e.,
signal) on its three semaphores. All semaphores are binary semaphores initialized to one.
Which one of the following represents a deadlock-free order of invoking the P operations by
the processes?
update certain shared variables. Process X executes the P operation (i.e., wait) on semaphores
a, b and c; process Y executes the P operation on semaphores b, c and d; process Z executes
the P operation on semaphores c, d, and a before entering the respective code segments. After
completing the execution of its code segment, each process invokes the V operation (i.e.,
signal) on its three semaphores. All semaphores are binary semaphores initialized to one.
Which one of the following represents a deadlock-free order of invoking the P operations by
the processes?
- a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)
- b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)
- c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)
- d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)
Correct answer is option 'B'. Can you explain this answer?
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Verified Answer
Three concurrent processes X, Y, and Z execute three different code se...
Suppose X performs P(b) and preempts, Y gets chance, but cannot do its first wait i.e., P(b),
so waits for X, now Z gets the chance and performs P(a) and preempts, next X gets chance.
X cannot continue as wait on ‘a’ is done by Z already, so X waits for Z. At this time Z can
continue its operations as down on c and d. Once Z finishes, X can do its operations and so Y.
In any of execution order of X, Y, Z one process can continue and finish, such that waiting is
not circular. In options (A),(C) and (D) we can easily find circular wait, thus deadlock
so waits for X, now Z gets the chance and performs P(a) and preempts, next X gets chance.
X cannot continue as wait on ‘a’ is done by Z already, so X waits for Z. At this time Z can
continue its operations as down on c and d. Once Z finishes, X can do its operations and so Y.
In any of execution order of X, Y, Z one process can continue and finish, such that waiting is
not circular. In options (A),(C) and (D) we can easily find circular wait, thus deadlock
Most Upvoted Answer
Three concurrent processes X, Y, and Z execute three different code se...
Deadlock-free order of invoking the P operations
To find a deadlock-free order of invoking the P operations, we need to ensure that no process is waiting indefinitely for a resource held by another process.
Given:
- Process X executes the P operation on semaphores a, b, and c
- Process Y executes the P operation on semaphores b, c, and d
- Process Z executes the P operation on semaphores c, d, and a
Analysis:
- Process X waits for semaphore a before executing its code segment. This means that process Y should not hold semaphore a before X can proceed.
- Process Y waits for semaphore b before executing its code segment. This means that process X should not hold semaphore b before Y can proceed.
- Process Z waits for semaphore c before executing its code segment. This means that process X should not hold semaphore c before Z can proceed.
- Process Z waits for semaphore a before executing its code segment. This means that process X should not hold semaphore a before Z can proceed.
- Process Y waits for semaphore c before executing its code segment. This means that process Z should not hold semaphore c before Y can proceed.
- Process Y waits for semaphore d before executing its code segment. This means that process Z should not hold semaphore d before Y can proceed.
Solution:
Based on the above analysis, a deadlock-free order of invoking the P operations is as follows:
- Process X: P(b), P(a), P(c)
- Process Y: P(d), P(b), P(c)
- Process Z: P(a), P(c), P(d)
In this order, each process waits for the semaphore that is not held by any other process, ensuring that no process is waiting indefinitely for a resource held by another process. Thus, option B is the correct answer.
To find a deadlock-free order of invoking the P operations, we need to ensure that no process is waiting indefinitely for a resource held by another process.
Given:
- Process X executes the P operation on semaphores a, b, and c
- Process Y executes the P operation on semaphores b, c, and d
- Process Z executes the P operation on semaphores c, d, and a
Analysis:
- Process X waits for semaphore a before executing its code segment. This means that process Y should not hold semaphore a before X can proceed.
- Process Y waits for semaphore b before executing its code segment. This means that process X should not hold semaphore b before Y can proceed.
- Process Z waits for semaphore c before executing its code segment. This means that process X should not hold semaphore c before Z can proceed.
- Process Z waits for semaphore a before executing its code segment. This means that process X should not hold semaphore a before Z can proceed.
- Process Y waits for semaphore c before executing its code segment. This means that process Z should not hold semaphore c before Y can proceed.
- Process Y waits for semaphore d before executing its code segment. This means that process Z should not hold semaphore d before Y can proceed.
Solution:
Based on the above analysis, a deadlock-free order of invoking the P operations is as follows:
- Process X: P(b), P(a), P(c)
- Process Y: P(d), P(b), P(c)
- Process Z: P(a), P(c), P(d)
In this order, each process waits for the semaphore that is not held by any other process, ensuring that no process is waiting indefinitely for a resource held by another process. Thus, option B is the correct answer.
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Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. Can you explain this answer?
Question Description
Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. 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 Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. Can you explain this answer?.
Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. 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 Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for GATE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. Can you explain this answer?.
Solutions for Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. Can you explain this answer? in English & in Hindi are available as part of our courses for GATE.
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Here you can find the meaning of Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. Can you explain this answer?, a detailed solution for Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. Can you explain this answer? has been provided alongside types of Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice Three concurrent processes X, Y, and Z execute three different code segments that access andupdate certain shared variables. Process X executes the P operation (i.e., wait) on semaphoresa, b and c; process Y executes the P operation on semaphores b, c and d; process Z executesthe P operation on semaphores c, d, and a before entering the respective code segments. Aftercompleting the execution of its code segment, each process invokes the V operation (i.e.,signal) on its three semaphores. All semaphores are binary semaphores initialized to one.Which one of the following represents a deadlock-free order of invoking the P operations bythe processes?a)X:P(a )P(b)P(c) Y:P(b )P(c)P(d) Z: P(c )P(d)P(a)b)X:P(b )P(a)P(c) Y:P(b )P(c)P(d) Z: P(a )P(c)P(d)c)X:P(b )P(a)P(c) Y:P(c )P(b)P(d) Z: P(a )P(c)P(d)d)X:P(a )P(b)P(c) Y:P(c )P(b)P(d) Z: P(c )P(d)P(a)Correct answer is option 'B'. Can you explain this answer? tests, examples and also practice GATE tests.
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