Deadlock detection and recovery in Operating Systems - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to identify the condition that causes a deadlock.

Operating Systems

if (resource_allocation == [1]) {
    // Deadlock detected
}

Drag options to blanks, or click blank then click option'

Acircular_wait

Bresource_available

Cno_wait

Dpreemption

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing resource availability with deadlock condition.

Thinking preemption alone causes deadlock.

The circular wait condition is one of the necessary conditions for a deadlock to occur. Detecting this condition helps identify deadlocks.

2fill in blank

medium

Complete the code to check if a process is part of a deadlock cycle.

Operating Systems

if (process_waits_for(process1, [1])) {
    // Process is in deadlock
}

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Aresource

Bprocess2

Ccpu

Dmemory

Attempts:

3 left

💡 Hint

Common Mistakes

Checking if process waits for a resource instead of another process.

Confusing CPU or memory as the waiting entity.

Deadlock involves processes waiting for other processes to release resources, so checking if process1 waits for process2 helps detect deadlock cycles.

3fill in blank

hard

Fix the error in the deadlock detection function by completing the missing condition.

Operating Systems

function detect_deadlock() {
    for each process in processes {
        if (process.state == [1]) {
            check_cycle(process);
        }
    }
}

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Arunning

Bready

Cterminated

Dwaiting

Attempts:

3 left

💡 Hint

Common Mistakes

Checking running or ready processes instead of waiting.

Including terminated processes in deadlock detection.

Only processes in the waiting state can be part of a deadlock, so the detection function should check those.

4fill in blank

hard

Fill both blanks to complete the recovery step after detecting deadlock.

Operating Systems

function recover_deadlock() {
    select [1] to terminate;
    release [2] held by it;
}

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Aprocess

Bresource

Cmemory

Dcpu

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to release CPU or memory directly instead of resources.

Terminating resources instead of processes.

Recovery from deadlock often involves terminating a process and releasing the resources it holds to break the deadlock cycle.

5fill in blank

hard

Fill all three blanks to complete the deadlock detection algorithm snippet.

Operating Systems

for each [1] in system {
    if ([2] waits for [3]) {
        mark as deadlocked;
    }
}

Drag options to blanks, or click blank then click option'

Aprocess

Bresource

Dthread

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing threads with processes.

Swapping resource and process in the wait condition.

The algorithm checks each process to see if it waits for a resource held by another process, indicating deadlock.