LAMMPS (10 Feb 2021)
# 3d Lennard-Jones melt

variable     x index 1
variable     y index 1
variable     z index 1

variable     xx equal 20*$x
variable     xx equal 20*1
variable     yy equal 20*$y
variable     yy equal 20*1
variable     zz equal 20*$z
variable     zz equal 20*1

units        real

lattice      fcc 4.4300
Lattice spacing in x,y,z = 4.4300000 4.4300000 4.4300000
region       box block 0 ${xx} 0 ${yy} 0 ${zz}
region       box block 0 20 0 ${yy} 0 ${zz}
region       box block 0 20 0 20 0 ${zz}
region       box block 0 20 0 20 0 20
create_box   1 box
Created orthogonal box = (0.0000000 0.0000000 0.0000000) to (88.600000 88.600000 88.600000)
  1 by 2 by 2 MPI processor grid
create_atoms 1 box
Created 32000 atoms
  create_atoms CPU = 0.001 seconds

pair_style   lj/cut 8.1500
pair_coeff   1 1 0.0104 3.4000

#pair_style  kim LennardJones_Ar
#pair_coeff  * * Ar

mass         1 39.95
velocity     all create 200.0 232345 loop geom

neighbor     0.3 bin
neigh_modify delay 0 every 1 check yes

fix          1 all nve
#fix         1 all npt temp 1.0 1.0 1.0 iso 1.0 1.0 3.0

run          100
Neighbor list info ...
  update every 1 steps, delay 0 steps, check yes
  max neighbors/atom: 2000, page size: 100000
  master list distance cutoff = 8.45
  ghost atom cutoff = 8.45
  binsize = 4.225, bins = 21 21 21
  1 neighbor lists, perpetual/occasional/extra = 1 0 0
  (1) pair lj/cut, perpetual
      attributes: half, newton on
      pair build: half/bin/atomonly/newton
      stencil: half/bin/3d/newton
      bin: standard
Per MPI rank memory allocation (min/avg/max) = 7.633 | 7.633 | 7.633 Mbytes
Step Temp E_pair E_mol TotEng Press 
       0          200    6290.8194            0    25367.408    6750.7421 
     100    98.747096    15900.676            0    25319.465    10184.453 
Loop time of 0.532082 on 4 procs for 100 steps with 32000 atoms

Performance: 16.238 ns/day, 1.478 hours/ns, 187.941 timesteps/s
99.8% CPU use with 4 MPI tasks x no OpenMP threads

MPI task timing breakdown:
Section |  min time  |  avg time  |  max time  |%varavg| %total
---------------------------------------------------------------
Pair    | 0.46077    | 0.46347    | 0.46621    |   0.3 | 87.10
Neigh   | 0.038499   | 0.038599   | 0.038759   |   0.0 |  7.25
Comm    | 0.01395    | 0.016623   | 0.019377   |   1.7 |  3.12
Output  | 3.1e-05    | 3.675e-05  | 4.7e-05    |   0.0 |  0.01
Modify  | 0.00787    | 0.007971   | 0.008083   |   0.1 |  1.50
Other   |            | 0.005382   |            |       |  1.01

Nlocal:        8000.00 ave        8012 max        7989 min
Histogram: 1 0 0 0 2 0 0 0 0 1
Nghost:        9131.00 ave        9142 max        9119 min
Histogram: 1 0 0 0 0 2 0 0 0 1
Neighs:        490066.0 ave      491443 max      489273 min
Histogram: 2 0 0 0 1 0 0 0 0 1

Total # of neighbors = 1960266
Ave neighs/atom = 61.258313
Neighbor list builds = 3
Dangerous builds = 0
Total wall time: 0:00:00