Download Cluster OpenMP User`s Guide

OpenMP* Usage with Cluster OpenMP*
-lguide
-lclusterguide and -lclompc
To ensure that you linked with the correct library, use the KMP_VERSION environment
variable as outlined in 10.5, Cluster OpenMP* Environment Variables. If you linked
correctly with Cluster OpenMP*, the version output should show Intel(R) Cluster OMP.
If not, the OpenMP* runtime library could be statically linked into the library you are
trying to use. In this the case, compile the program to produce object files and link
explicitly as follows:
<intel compiler> <obj files> -o <exe> –lclusterguide –lclompc –
l<other library>
As long as –lclusterguide appears before the other library on the link line, the
OpenMP* runtime library symbols will be resolved from the Cluster OpenMP* runtime
library instead of from the other library you are trying to use. To verify, use
KMP_VERSION to make sure you linked with Cluster OpenMP*. If you linked correctly
with Cluster OpenMP*, the version output should show Intel(R) Cluster OMP.
10.3
OpenMP* Implementation-Defined Behaviors
in Cluster OpenMP*
The OpenMP* specification at www.openmp.org requires an implementation to
document its behavior in a certain set of cases. This section documents these
behaviors for Cluster OpenMP.
10.3.1
Number of Threads to Use for a Parallel Region
The number of OpenMP threads that are started at the beginning of a given program
is the value of the omp_num_threads option after proper defaults are applied. This is
the maximum number of threads that can be used by any parallel region in the
program.
A parallel region can use fewer than the maximum number of threads by specifying a
value for the OMP_NUM_THREADS environment variable, or by using the
omp_set_num_threads() routine.
10.3.2
Number of Processors
The number of processors reported by omp_get_num_procs() is the sum of the
number of processors on all nodes.
User Manual
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