32.5.8 Load Distribution

If the speeds of the processors that will be used for a parallel calculation differ significantly, you can specify a load distribution for partitioning, using the load-distribution text command.

parallel $\rightarrow$ partition $\rightarrow$ set $\rightarrow$ load-distribution

For example, if you will be solving on three compute nodes, and one machine is twice as fast as the other two, then you may want to assign twice as many cells to the first machine as to the others (i.e., a load vector of (2 1 1)). During subsequent mesh partitioning, partition 0 will end up with twice as many cells as partitions 1 and 2.

Note that for this example, you would then need to start up ANSYS FLUENT such that compute node 0 is the fast machine, since partition 0, with twice as many cells as the others, will be mapped onto compute node 0. Alternatively, in this situation, you could enable the load balancing feature (described in Section  32.5.5) to have ANSYS FLUENT automatically attempt to discern any difference in load among the compute nodes.

If you adapt a mesh that contains non-conformal interfaces, and you want to rebalance the load on the compute nodes, you will have to save your case and data files after adaption, read the case and data files into the serial solver, repartition using the Encapsulate Mesh Interfaces and Encapsulate for Adaption options in the Partitioning and Load Balancing dialog box, and save case and data files again. You will then be able to read the manually repartitioned case and data files into the parallel solver, and continue the solution from where you left it.