Editing Deadlock (computer science) (section)

==Distributed deadlock==
''Distributed deadlocks'' can occur in [[distributed systems]] when [[distributed transaction]]s or [[concurrency control]] is being used.

Distributed deadlocks can be detected either by constructing a global [[wait-for graph]] from local wait-for graphs at a deadlock detector or by a [[distributed algorithm]] like edge chasing.

''Phantom deadlocks'' are deadlocks that are falsely detected in a distributed system due to system internal delays but do not actually exist. For example, if a process releases a resource ''R1'' and issues a request for ''R2'', and the first message is lost or delayed, a coordinator (detector of deadlocks) could falsely conclude a deadlock (if the request for ''R2'' while having ''R1'' would cause a deadlock).