MPI_Reduce-nodes

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MPI_Reduce-nodes

Here me measure the time MPI_Reduce consumes. This operation performes a global operation (here: bit-wise or) on all participating processes. We vary over the number of nodes.

$\epsfig{file=col_MPI_Reduce-nodes.eps}$

Pattern: Collective varied over number of nodes.
default values: 8 nodes, message length 256 units, max. / act. time for suite disabled/0.00 min.
Max. allowed standard error is 3.00 %.

	number of nodes
X axis scale	linear
Param. refinement	no automatic x wide adaption
Argument range	2 - 8 units (s. below)
Argument stepwidth	1.000000

Units: number, basetype 1 (MPI_INT), send-datatype 20: size 4 Bytes, extent 4 Bytes (user defined basetype 1 (MPI_INT)), receive-datatype 20: size 4 Bytes, extent 4 Bytes (user defined basetype 1 (MPI_INT))

Per Ekman 2002-01-29