A lock incorporating a deadbolt.
Deadlock occurs within a real-time system (or any system for that matter) when the system is unable to proceed with its work due to a problem accessing critical resources. The classic example occurs when: process A gets lock 1, process B gets lock 2, process A attempts to get lock 2, and process B attempts to get lock 1. A and B are competing for the same locks and neither one will let the other progress. Deadlock has occurred.
Occurs in a network when two users both try to access a file the other has locked.
When a complete impasse is reached in a parliamentary debate, or disagreement between the Houses.
A state in which every process in a set of processes is waiting for an event or resource that only another process in the set can provide. For example, in data communications, a deadlock can occur when both the sending and receiving sockets are waiting on each other, or for a common resource.
Occurs when a set of processes are blocked waiting requests that CAN NEVER BE SATISFIED
A deadlock occurs when multiple threads each attempt to acquire multiple locks, and the system cannot make progress due to dependencies. The simplest case is that thread _A_ has lock _U_ and tries to acquire lock _V_, while at the same time thread _B_ has lock _V_ and tries to acquire lock _U_.
Occurs when one user has locked a data page and tries to lock another page or row that is locked by a second user who, in turn, is trying to lock the page or row that is locked by the first user. While such occurrences are rare, the longer that a page, row, table, or file is locked, the greater the chance of a deadly embrace (an unresolved deadlock condition that blocks two or more applications). .
Deadlock is a condition in which two or more mutually dependent processes are prevented by their dependence from proceeding. The states in which no further protocol execution is possible, for instance because all protocol processes are waiting for conditions that can never be fulfilled. For example, if four cars simultaneously arrive at an intersection, they could theoretically remain there forever. Deadlock is generally considered something to avoid.
When two or more processes are waiting for locks held by each other.
Unresolved contention for the use of a resource.
The situation in which two processes each wait for the other to finish a task before continuing. If each waits for the other, neither can continue.
A single bolt mortice lock which can be used to supplement a standard cylinder rim lock on the front door.
A situation where shareholders factions can block corporate action; often arises when there is a split between two factions over electing directors
a situation in which no progress can be made or no advancement is possible; "reached an impasse on the negotiations"
a bad locking situation that could occur when not properly placing locks in a transaction
a circular waiting situation, which can involve many transactions, not just two
a condition that occurs when two processes are each waiting for the other to complete before proceeding
a condition that occurs when two threads attempt to access a resource that has already been locked by them
a condition where two or more users are waiting for data locked by each other
a lock that has to be deliberately locked with a key or thumbturn
a situation in which a pair of programs block the progress of each other
a situation in which a set of threads are all waiting for resources taken by other threads, all in the same set
a situation in which clients are blocked, each waiting for resources held by the other
a situation in which two or more processes are all waiting for an event that only the other processes can cause
a situation in which two transactions conflict with each other and the only resolution is to cancel one of the transactions
a situation when a set of entities in a simulation, holding some resources, all request access to resources held by other entities in the same set
a situation where one or more threads are forever blocking each other
a situation where threads are blocked because one or both are waiting for access to a resource that will not be freed
a state in which no request can execute the locked section of a page
Deadlocks occur when two or more processes hold a resource that the other one needs. Neither of the processes will release its resource until it has received the other's resource; therefore, neither process can proceed.
A lock incorporating an unsprung bolt, usually rectangular in shape, which is locked and unlocked by key only. Alternatively, a thumbturn can be used to provide free exit.
A condition where two separate threads acquire a target resource simultaneously, but the action to be taken by each thread is blocked by the other.
A situation in parallel computers where all activities are blocked, typically while waiting for something which is also blocked. This usually signals an error in the communication code.
When multiple threads acquire each others' needed locks but can't release those locks because they are both waiting to enter their respective critical code sections.
A lock that incorporates a deadbolt.
Irresolvable contention for a requested resource.
In operating systems, a situation in which two or more processes are blocked while waiting for resources that the other controls so that none of the affected processes can continue to execute. Also known as the "deadly embrace."
A bug where the execution of thread A is blocked indefinitely waiting for thread B to perform some action, while thread B is blocked waiting for thread A. For example, two threads on opposite ends of a named pipe can become deadlocked if each thread waits to read data written by the other thread. A single thread can also deadlock itself. See also thread.
A lock which is locked and unlocked by the key only. The exception to this is a fire escape lock which can be unlocked from the inside, usually using a handle.
(n.) A situation that describes two or more processes that are waiting for another process to free a resource which is required to proceed. Also called deadly embrace.
A deadlock is a programming error that causes two or more kernel threads to be indefinitely blocked. Specifically, the error occurs when a kernel thread holds a resource while waiting for a resource held by another kernel thread and that kernel thread is also waiting for the first kernel thread's resource.
A lock that requires a key to open from the outside and a turn bolt from the inside, which slides into a receptacle in the doorjamb. It is also called a dead bolt or a deadbolt lock.
A condition in which one or more threads are unable to continue due to resource contention. A common form of deadlock can occur when one thread sends a message to another, while the other thread sends a message to the first. Both threads are now waiting for each other to reply to the message. Deadlock can be avoided by good design practices or massive kludges -- we recommend the good design approach.
A lock in which the bolt is fixed in its locked position such that the bolt cannot be pushed back into the lock using normal pressure.
A lock equipped with a deadbolt only.
A lock equipped with a dead bolt only.
A standard deadbolt lock that is operated by key, thumbturn, or combination of both.
A situation in which each possible activity is blocked, waiting on some other activity that is also blocked.
The conflict state where two or more synchronized Java objects depend on locking each other, but cannot, because they themselves are locked by the dependent object. For example, object A tries to lock object B while object B is trying to lock object A. This situation is difficult to debug, because a preemptive Java virtual machine can neither detect nor prevent deadlock. Without deadlock detection, a deadlocked program simply hangs.
Any of a number of situations where two or more processes cannot proceed because they are both waiting for the other to release some resource. FIXME(give good references).
The condition in which two or more processes are blocked, each waiting for a lock held by the other. Deadlock is prevented by the rule that a driver upper-half entry point is not allowed to hold a lock while sleeping.
a situation where two sides cannot reach an agreement. Some contracts and agreements contain deadlock clauses, which deal with changes of circumstances where the parties cannot agree and stop one side from imposing its will on the other. Usually accompanied by an arbitration (see above) clause.
Condition involving one or more threads and a set of one or more resources in which each of the threads is blocked waiting for one of the resources and all of the resources are held by the threads such that none of the threads can continue. For example, a thread will enter a self-deadlock when it attempts to lock a "fast" mutex a second time. Likewise, two threads will enter a deadlock when each attempts to lock a second mutex that is already held by the other. The introduction of additional threads and synchronization objects allows for more complex deadlock configurations.
A situation in which two or more users of a database cannot complete their transactions, because each user is holding a resource that the other user requires in order to complete. The ORACLE Server automatically avoids and resolves deadlocks.
A condition where two or more processes are waiting for an event or communication from one of the other processes.
A situation in which processors of a concurrent processor are waiting on an event which will never occur. A simple version of deadlock for a loosely synchronous environment arises when blocking reads and writes are not correctly matched. For example, if two nodes both execute blocking writes to each other at the same time, deadlock will occur since neither write can complete until a complementary read is executed in the other node.
standard mortice lock, set into the edge of a door, with a square-ended bolt operated by key or, occasionally, by a thumb turn on the inside.
The situation in which two communicating processes are each waiting for the other to perform an action.
A situation that occurs when the upper and lower houses of parliament fail to agree on an issue, obstructing the passage of legislation.
n. a lock which incorporates a deadbolt
A situation in which computer processing is suspended because two or more devices or processes are each awaiting resources assigned to the other. (IEEE Standard 610.12-1990)
an occurrence where two computer processes are waiting for the other to finish, keeping each from proceeding.
An unwanted software situation in which an entire set of tasks is blocked, waiting for an event that only a task within the same set can cause. If a deadlock occurs, the only solution is to reset the involved set of tasks or the entire system. However, it is usually possible to prevent deadlocks altogether by following certain software-design practices. Consult an operating systems textbook for details. A key condition for deadlock is a circular wait, such as that shown here.
A deadlock is a situation wherein two or more competing actions are waiting for the other to finish, and thus neither ever does. It is often seen in a paradox like 'the chicken or the egg'.