What is a deadlock? How to know if a deadlock is present?

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A deadlock is a situation where two or more processes are unable to proceed because they are waiting for each other to release resources.

Deadlocks occur when two or more processes are blocked and unable to continue executing.
To detect a deadlock, look for circular wait, hold and wait, no preemption, and mutual exclusion.
Examples of deadlocks include a printer that is waiting for a user to replace the paper tray, or two trains that are stuck on the same track waiting for each other to move.
Deadlocks can be prevented by using techniques such as resource allocation graphs, banker's algorithm, and timeouts.

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### **What is a Deadlock?** A **deadlock** is a situation in computing where two or more processes are stuck because each is waiting for a resource that another process is holding. This creates a cycle where no process can proceed, leading to system inefficiency[43dcd9a7-70db-4a1f-b0ae-981daa162054]( https://www.geeksforgeeks.org/conditions-for-deadlock-in-operating-system/?citationMarker=43dcd9a7-70db-4a1f-b0ae-981daa162054 "1")[43dcd9a7-70db-4a1f-b0ae-981daa162054]( https://www.baeldung.com/cs/os-deadlock?citationMarker=43dcd9a7-70db-4a1f-b0ae-981daa162054 "2"). ### **How to Detect a Deadlock?** Deadlocks can be identified using various techniques: 1. **Resource Allocation Graph (RAG)**: If a cycle exists in the graph, a deadlock may be present. 2. **Deadlock Detection Algorithm**: The system periodically checks for circular dependencies among processes. 3. **Process Monitoring**: If processes remain indefinitely in a waiting state, a deadlock might have occurred. Deadlocks can be **prevented** or **resolved** using strategies like resource ordering, preemption, or process termination[43dcd9a7-70db-4a1f-b0ae-981daa162054]( https://www.baeldung.com/cs/os-deadlock?citationMarker=43dcd9a7-70db-4a1f-b0ae-981daa162054 "2")[43dcd9a7-70db-4a1f-b0ae-981daa162054]( https://www.tutorialspoint.com/operating_system/introduction_to_deadlock_in_operating_system.htm?citationMarker=43dcd9a7-70db-4a1f-b0ae-981daa162054 "3"). Would you like to explore deadlock prevention methods? 😃

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डेडलॉक। यह कंप्यूटर विज्ञान में ऐसी स्थिति है जहाँ दो या अधिक प्रक्रियाएँ अनिश्चित काल के लिए अवरुद्ध हो जाती हैं, प्रत्येक प्रक्रिया दूसरे द्वारा संसाधन जारी करने की प्रतीक्षा करती है। डेडलॉक की मौजूदगी का पता कैसे लगाएं: 1. पारस्परिक बहिष्कार 2. होल्ड और प्रतीक्षा 3. कोई पूर्वग्रहण नहीं 4. परिपत्र प्रतीक्षा

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deadlock occurs when two or more tasks permanently black each other by task having a lock on a resource that the other tasks trying to lock. Deadlock if all

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deadlock by observing a circular dependency where each process is waiting for a resource held by another process in the cycle, effectively blocking all involved processes. 
deadlock by observing a circular dependency where each process is waiting for a resource held by another process in the cycle, effectively blocking all involved processes.

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deadlock occurs when two or more tasks permanently black each other by task having a lock on a resource that the other tasks trying to lock. Deadlock if all

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deadlock is a situation where two or more processes are unable to proceed because they are waiting for each other to release resources.Deadlocks occur when two or more processes are blocked

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Deadlock. This is situation in computer science where two or more processes are blocked indefinitely, each waiting for the other to release a resource.
 How to know if a deadlock is present:
1. Mutual exclusion
2. Hold and wait 
3. No preemption
4. Circular wait

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A deadlock occurs when two or more tasks permanently black each other by task having a lock on a resource that the other tasks trying to lock. 
Deadlock if all thread pick up their lift chopstick before any thread picks up the right chopstick.

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A deadlock occurs when two or more tasks permanently black each other by task having a lock on a resource that the other tasks trying to lock. 
Deadlock if all thread pick up their lift chopstick before any thread picks up the right chopstick.

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Work process

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Deadlock detection
Make a copy of the resource allocation graph.
While there is a process or resource with no outgoing edge: ...
If you can remove all processes, there is no deadlock: you can run all processes to completion.
If you can't, then there must be a cycle, so the system is deadlocked.

What is a deadlock? How to know if a deadlock is present?

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