Allreduce
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allreduce[operation]
Semantics
Similar to the reduce type, but the reduction will be performed on each process and the result is also available to all.
Example
var x:Int::allocated[multiple[]];
var p;
par p from 0 to 3
{
(x::allreduce["min"]):=p;
};
In this case all processes will perform the reduction on p and all processes will have the minimum value of p placed into their copy of x.
Supported operations
| Operator | Description |
|---|---|
| max | Identify the maximum value |
| min | Identify the minimum value |
| sum | Sum all the values together |
| prod | Generate product of all values |
