lammps/doc/comm_style.txt

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"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
:link(lws,http://lammps.sandia.gov)
:link(ld,Manual.html)
:link(lc,Section_commands.html#comm)
:line
comm_style command :h3
[Syntax:]
comm_style style :pre
style = {brick} or {tiled} :ul
[Examples:]
comm_style brick
comm_style tiled :pre
[Description:]
This command sets the style of inter-processor communication of atom
information that occurs each timestep as coordinates and other
properties are exchanged between neighboring processors and stored as
properties of ghost atoms.
For the default {brick} style, the domain decomposition used by LAMMPS
to partition the simulation box must be a regular 3d grid of bricks,
one per processor. Each processor communicates with its 6 Cartesian
neighbors in the grid to acquire information for nearby atoms.
For the {tiled} style, a more general domain decomposition can be
used, as triggered by the "balance"_balance.html or "fix
balance"_fix_balance.html commands. The simulation box can be
partitioned into non-overlapping rectangular-shaped "tiles" or varying
sizes and shapes. Again there is one tile per processor. To acquire
information for nearby atoms, communication must now be done with a
more complex pattern of neighboring processors.
Note that this command does not actually define a partitoining of the
simulation box (a domain decomposition), rather it determines what
kinds of decompositions are allowed and the pattern of communication
used to enable the decomposition. A decomposition is created when the
simulation box is first created, via the "create_box"_create_box.html
or "read_data"_read_data.html or "read_restart"_read_restart.html
commands. For both the {brick} and {tiled} styles, the initial
decomposition will be the same, as described by
"create_box"_create_box.html and "processors"_processors.html
commands. The decomposition can be changed via the
"balance"_balance.html or "fix balance"_fix_balance.html commands.
[Restrictions:] none
[Related commands:]
"comm_modify"_comm_modify.html, "processors"_processors.html,
"balance"_balance.html, "fix balance"_fix_balance.html
[Default:]
The default style is brick.