MPI_Barrier-nodes

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MPI_Barrier-nodes

This test synchronizes several processes via MPI_Barrier. This measurement ist interesting because this operation usually is called very often. We vary over the number of nodes. (Since there are no longer messages sent, we cannot vary over message length.)

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

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