enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Two-phase locking - Wikipedia

    en.wikipedia.org/wiki/Two-phase_locking

    The protocol uses locks, applied by a transaction to data, which may block (interpreted as signals to stop) other transactions from accessing the same data during the transaction's life. By the 2PL protocol, locks are applied and removed in two phases: Expanding phase: locks are acquired and no locks are released.

  3. Chandy–Misra–Haas algorithm resource model - Wikipedia

    en.wikipedia.org/wiki/Chandy–Misra–Haas...

    occurrence of deadlock in distributed system. P 1 initiates deadlock detection. C 1 sends the probe saying P 2 depends on P 3. Once the message is received by C 2, it checks whether P 3 is idle. P 3 is idle because it is locally dependent on P 4 and updates dependent 3 (2) to True. As above, C 2 sends probe to C 3 and C 3 sends probe to C 1.

  4. Wait-for graph - Wikipedia

    en.wikipedia.org/wiki/Wait-For_Graph

    A wait-for graph in computer science is a directed graph used for deadlock detection in operating systems and relational database systems.. In computer science, a system that allows concurrent operation of multiple processes and locking of resources and which does not provide mechanisms to avoid or prevent deadlock must support a mechanism to detect deadlocks and an algorithm for recovering ...

  5. Lock (computer science) - Wikipedia

    en.wikipedia.org/wiki/Lock_(computer_science)

    Careless use of locks can result in deadlock or livelock. A number of strategies can be used to avoid or recover from deadlocks or livelocks, both at design-time and at run-time. (The most common strategy is to standardize the lock acquisition sequences so that combinations of inter-dependent locks are always acquired in a specifically defined ...

  6. Ostrich algorithm - Wikipedia

    en.wikipedia.org/wiki/Ostrich_algorithm

    This approach may be used in dealing with deadlocks in concurrent programming if they are believed to be very rare and the cost of detection or prevention is high. A set of processes is deadlocked if each process in the set is waiting for an event that only another process in the set can cause.

  7. Deadlock prevention algorithms - Wikipedia

    en.wikipedia.org/wiki/Deadlock_prevention_algorithms

    In computer science, deadlock prevention algorithms are used in concurrent programming when multiple processes must acquire more than one shared resource. If two or more concurrent processes obtain multiple resources indiscriminately, a situation can occur where each process has a resource needed by another process.

  8. Safety and liveness properties - Wikipedia

    en.wikipedia.org/wiki/Safety_and_liveness_properties

    Deadlock freedom is a safety property: the "bad thing" is a deadlock (which is discrete). Most of the time, knowing that a program eventually does some "good thing" is not satisfactory; we want to know that the program performs the "good thing" within some number of steps or before some deadline.

  9. Readers–writer lock - Wikipedia

    en.wikipedia.org/wiki/Readers–writer_lock

    Upgrading a lock from read-mode to write-mode is prone to deadlocks, since whenever two threads holding reader locks both attempt to upgrade to writer locks, a deadlock is created that can only be broken by one of the threads releasing its reader lock. The deadlock can be avoided by allowing only one thread to acquire the lock in "read-mode ...