Special issues for heterogeneous networks
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When building MPICH for a heterogeneous collection of workstations, you may want to configure with the option -no_short_longs. This indicates to MPICH that it should not provide support for the C type long double. This can improve performance between systems that have the same datatype lengths for all other types (some Intel x86 machines have 12 byte long doubles; many other systems use either 8 or 16 byte long doubles).
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Up: Configuring mpich Next: Compiling mpich Previous: What if there is no Fortran compiler?