Search results
Results from the WOW.Com Content Network
In computer science, mutual exclusion is a property of concurrency control, which is instituted for the purpose of preventing race conditions. It is the requirement that one thread of execution never enters a critical section while a concurrent thread of execution is already accessing said critical section, which refers to an interval of time ...
Most modern processors have special instructions, which, by locking the memory bus, can be used to guarantee atomicity and provide mutual exclusion in SMP systems. Examples include test-and-set (XCHG) and compare-and-swap (CMPXCHG) on x86 processors and load-link/store-conditional on Alpha, MIPS, PowerPC, and other architectures.
In computer science, a lock or mutex (from mutual exclusion) is a synchronization primitive that prevents state from being modified or accessed by multiple threads of execution at once. Locks enforce mutual exclusion concurrency control policies, and with a variety of possible methods there exist multiple unique implementations for different ...
Mutual exclusion: The Banker's algorithm is a resource allocation and deadlock avoidance algorithm developed by Edsger Dijkstra. Preventing recursive locks: Mutual exclusion: This prevents a single thread from entering the same lock more than once.
The term race condition was already in use by 1954, for example in David A. Huffman's doctoral thesis "The synthesis of sequential switching circuits". [1] Race conditions can occur especially in logic circuits or multithreaded or distributed software programs. Using mutual exclusion can prevent race conditions in distributed software systems.
Lamport's bakery algorithm is a computer algorithm devised by computer scientist Leslie Lamport, as part of his long study of the formal correctness of concurrent systems, which is intended to improve the safety in the usage of shared resources among multiple threads by means of mutual exclusion.
In computer architecture, the test-and-set CPU instruction (or instruction sequence) is designed to implement mutual exclusion in multiprocessor environments. Although a correct lock can be implemented with test-and-set, the test and test-and-set optimization lowers resource contention caused by bus locking, especially cache coherency protocol overhead on contended locks.
Dekker's algorithm is the first known correct solution to the mutual exclusion problem in concurrent programming where processes only communicate via shared memory. The solution is attributed to Dutch mathematician Th. J. Dekker by Edsger W. Dijkstra in an unpublished paper on sequential process descriptions [1] and his manuscript on cooperating sequential processes. [2]