[lammps-users] Question about running programs on parallel

Hi all LAMMP users
I am trying to run my simulations (with Granular package)on parallel computers. I could able run them many days ago.but for my new simulations, the speed of my runs is very slow(in new LAMMPS version) and I checked it and saw that I had no difference in rate of running my simulations with 8 computers or 32 ones and it is very interesting for me and I don’t know where is my mistake.I will be glad if help me in my problem.
With the best regards
Hamed Maleki

Hamed Maleki
1. Physics Department, Faculty of Science, University of Birjand, 97175- 615, Shokat abad, Birjand, Southern Khorasan Providence,Iran
2. Physics Department, Institute for Advanced Studies in Basic Sciences (IASBS), 45195-1159, Gava zang, Zanjan, Zanjan Providence, Iran
Home Page: http://hamedmaleki2000.googlepages.com

There's lots of reasons a particular simulation might show little
speed-up when going from 8 to 32 procs. Too few atoms/proc.
Load-imbalance where some procs have none or few atoms. Too
much output, etc. Looking at the timing breakdown LAMMPS prints
out should help you figure out where the time is being spent.