In computer science, a parallel random-access machine (PRAM) is a shared-memory abstract machine. As its name indicates, the PRAM was intended as the parallel-computing analogy to the random-access machine (RAM). In the same way, that the RAM is used by sequential-algorithm designers to model algorithmic performance (such as time complexity), the PRAM used by parallel-algorithm designers to model parallel algorithmic performance (such as time complexity, where the number of processors assumed is typically also stated). Similar to the way in which the RAM model neglects practical issues, such as access time to cache memory versus main memory, the PRAM model neglects such issues as synchronization and communication, but provides any (problem-size-dependent) number of processors. Algorithm cost, for instance, is estimated using two parameters O(time) and O(time × processor_number).
Read more about Parallel Random-access Machine: Read/write Conflicts, Implementation, Example Code
Famous quotes containing the words parallel and/or machine:
“One writes of scars healed, a loose parallel to the pathology of the skin, but there is no such thing in the life of an individual. There are open wounds, shrunk sometimes to the size of a pin-prick but wounds still. The marks of suffering are more comparable to the loss of a finger, or the sight of an eye. We may not miss them, either, for one minute in a year, but if we should there is nothing to be done about it.”
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