Hi,
I finally got lammps to work on a linux box parallely on 2 processors. But I have a situation here. When I tried to run an example simulation of the melt, I ran on the 2 processors indivudally. (i.e.) the whole sim was run on both separately. Here is the output from the screen. Can some one explain this to me. I was thinking lammps would divide the job and reduce the time by atleast half.
[venkat@…157… venkat] mpdtrace
node2
node3
[[email protected]... venkat] cd lammps
[venkat@…157… lammps] cd examples/
[[email protected]... examples] cd melt/
[venkat@…157… melt] mpdtrace
node2
node3
[[email protected]... melt] mpiexec -n 2 lmp_linpol <in.melt
LAMMPS (12 Apr 2006)
LAMMPS (12 Apr 2006)
Created box = (0 0 0) to (33.5919 33.5919 33.5919)
Created box = (0 0 0) to (33.5919 33.5919 33.5919)
1 by 1 by 1 processor grid
1 by 1 by 1 processor grid
Created 32000 atoms
Created 32000 atoms
Setting up run …
Setting up run …
Memory usage per processor = 14.8211 Mbytes
Step Temp E_pair E_mol TotEng Press
Memory usage per processor = 14.8211 Mbytes
Step Temp E_pair E_mol TotEng Press
0 3 -6.7733681 0 -2.2735087 -3.7027964
0 3 -6.7733681 0 -2.2735087 -3.7027964
50 1.6634568 -4.7767061 0 -2.2815989 5.7060587
50 1.6634568 -4.7767061 0 -2.2815989 5.7060587
100 1.6411943 -4.741815 0 -2.2801004 5.8702166
100 1.6411943 -4.741815 0 -2.2801004 5.8702166
150 1.6434235 -4.7448489 0 -2.2797906 5.868853
150 1.6434235 -4.7448489 0 -2.2797906 5.868853
200 1.6427413 -4.7436699 0 -2.279635 5.8804726
200 1.6427413 -4.7436699 0 -2.279635 5.8804726
250 1.6373146 -4.7362602 0 -2.2803651 5.8998494
250 1.6373146 -4.7362602 0 -2.2803651 5.8998494
Loop time of 36.9314 on 1 procs for 250 steps with 32000 atoms
Pair time () = 28.1954 (76.3454)
Neigh time () = 2.62167 (7.09875)
Comm time () = 0.606915 (1.64336)
Outpt time () = 4.19489 (11.3586)
Other time () = 1.3125 (3.55387)
Nlocal: 32000 ave 32000 max 32000 min
Histogram: 1 0 0 0 0 0 0 0 0 0
Nghost: 18806 ave 18806 max 18806 min
Histogram: 1 0 0 0 0 0 0 0 0 0
Neighs: 1.21276e+06 ave 1.21276e+06 max 1.21276e+06 min
Histogram: 1 0 0 0 0 0 0 0 0 0
Total # of neighbors = 1212760
Ave neighs/atom = 37.8987
Neighbor list builds = 12
Dangerous builds = 0
Loop time of 36.9336 on 1 procs for 250 steps with 32000 atoms
Pair time () = 28.174 (76.2827)
Neigh time () = 2.64747 (7.16818)
Comm time () = 0.632862 (1.71351)
Outpt time () = 4.14881 (11.2331)
Other time () = 1.33054 (3.60251)
Nlocal: 32000 ave 32000 max 32000 min
Histogram: 1 0 0 0 0 0 0 0 0 0
Nghost: 18806 ave 18806 max 18806 min
Histogram: 1 0 0 0 0 0 0 0 0 0
Neighs: 1.21276e+06 ave 1.21276e+06 max 1.21276e+06 min
Histogram: 1 0 0 0 0 0 0 0 0 0
Total # of neighbors = 1212760
Ave neighs/atom = 37.8987
Neighbor list builds = 12
Dangerous builds = 0