Cloud Computing (CC) - Arquitectura de Sistemas Computacionais
Cloud Computing (CC) - Arquitectura de Sistemas Computacionais
Cloud Computing (CC) - Arquitectura de Sistemas Computacionais
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Collective Operations- Overall<br />
a global view of a computation to <strong>de</strong>scribe simple patterns of<br />
cooperation<br />
- Executed jointly by all or a subset of processing elements (PE)<br />
- Can be combined with data//, task//, sharedMem, Msg, etc<br />
- Operations must be collectively invoked by all partners<br />
- Ease program <strong>de</strong>sign; allow more efficient implementations,<br />
- Ease performance portability<br />
Ex: most usual are Broadcast and Multicast<br />
Ex: Reduction – combines multiple values from multiple PE into a single value<br />
at a single PE<br />
(ops can be add, mul, AND, OR, max, min, or User.<strong>de</strong>fined)<br />
ops must be associative and commutative<br />
Ex: also usual is Barrier synchronization<br />
Ex: Scatter and Gather for distributed memory architectures, eg as in MPI<br />
distribute a set of data to several PE / collect multiple data sets from PE into a single value<br />
in a PE<br />
JCunha<br />
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