Linear Algebra Settings

The number of CPUs and the algorithm of the linear algebra part of Turbomole depends on the settings of $parallel_platform:

cluster

- for clusters with TCP/IP interconnect. Communication is avoided by using an algorithm that includes only one or few CPUs.

MPP

- for clusters with fast interconnect like Infiniband or Myrinet. Number of CPUs that take part at the calculation of the linear algebra routines depends on the size of the input and the number of nodes that are used.

SMP

- all CPUs are used and SCALapack (see http://www.netlib.org/scalapack/) routines are involved.

The scripts in $TURBODIR/mpirun_scripts automatically set this keyword depending on the output of sysname. All options can be used on all systems, but especially the SMP setting can slow down the calculation if used on a cluster with high latency or small bandwidth.