Deadlock prevention

1. What is a deadlock and how can it be avoided?
2. What should not be done to avoid deadlock?
3. What are four general strategies for dealing with deadlocks?
4. How can the hold and wait condition be prevented?
5. What are the causes of deadlock?
6. What are two methods of synchronization?
7. Can a deadlock happen with three threads?
8. What is the default thread priority?
9. Which process is used as a victim in a deadlock situation?
10. When a transaction is said to be deadlocked?

What is a deadlock and how can it be avoided?

In order to avoid deadlock, you have to acquire a lock in the fixed order. ... Once process1 commits the transaction successfully, it will release the locks on the resources; therefore process 2 will get the required resources in order to complete the transaction successfully without getting into the deadlock.

What should not be done to avoid deadlock?

What should not be done to avoid deadlock? Explanation: To avoid deadlock situation in Java programming do not execute foreign code while holding a lock.

What are four general strategies for dealing with deadlocks?

Mutual exclusion, hold-and-wait, no pre-emption and circular-wait are the four necessary conditions for a deadlock to occur. If one of these conditions can never be satisfied then deadlock can be prevented. For this there are three prevention methods namely: I.

How can the hold and wait condition be prevented?

– The hold andwait condition can be prevented by requiring that a process request all its required resources at one time, and blocking the process until all requests can be granted simultaneously.

What are the causes of deadlock?

A deadlock occurs when 2 processes are competing for exclusive access to a resource but is unable to obtain exclusive access to it because the other process is preventing it. This results in a standoff where neither process can proceed. The only way out of a deadlock is for one of the processes to be terminated.

What are two methods of synchronization?

There are two types of thread synchronization mutual exclusive and inter-thread communication. Synchronized method. Synchronized block. Static synchronization.

Can a deadlock happen with three threads?

Thread Deadlock

Deadlock can occur when multiple threads need the same locks, at the same time, but obtain them in different order.

What is the default thread priority?

Default priority of a thread is 5 (NORM_PRIORITY).

Which process is used as a victim in a deadlock situation?

The process with the lowest deadlock priority is set as deadlock victim. If the deadlock priority of all the processes involved in deadlock is same, then the process that is least expensive to rollback is selected as deadlock victim.

When a transaction is said to be deadlocked?

A deadlock occurs if each of two transactions (for example, A and B) needs exclusive use of some resource (for example, a particular record in a data set) that the other already holds. Transaction A waits for the resource to become available.