SPPARKS Website - SPPARKS Documentation - SPPARKS Commands

processors command

Syntax:

processors Px Py Pz 

Examples:

processors 2 4 4 

Description:

Specify how processors are mapped as a 3d logical grid to the global simulation box for spatial on-lattice or off-lattice models.

When this command has not been specified, SPPARKS will choose Px, Py, Pz based on the dimensions of the global simulation box so as to minimize the surface/volume ratio of each processor's sub-domain.

Since SPPARKS does not load-balance by changing the grid of 3d processors on-the-fly, this command should be used to override the SPPARKS default if it is known to be sub-optimal for a particular problem.

The product of Px, Py, Pz must equal P, the total # of processors SPPARKS is running on. If multiple partitions are being used then P is the number of processors in this partition; see this section for an explanation of the -partition command-line switch.

If P is large and prime, a grid such as 1 x P x 1 will be required, which may incur extra communication costs.

Restrictions:

This command must be used before the simulation box is defined by a read_sites or create_box command.

Related commands: none

Default:

SPPARKS chooses Px, Py, Pz