The ghost particle cell list creates a shell of "ghost particles" around the simulation cell. This eliminates the need to apply periodic boundary conditions every time step; PBC are applied only when the neighborlist is updated.
Dense LJ Fluid (rho=0.85), check every time, code revision 440
Brownian Dynamics LJ system with number density 0.85, T=1.0, and skin=0.375. The system checks every time step to see if a the neighborlist needs to be updated. Neighborlist updates occur every ~5-7 timesteps.
Timings are the number of seconds to run 10000 timesteps scaled by the number of particles.
- Run on AON (2.0 GHz Apple G5).
| Number of Particles | Total Cells | Verlet List Timing | Verlet List w/Ghost Particles Timing
|
| 1000 | 27 | 0.1776 | 0.1567
|
| 2744 | 125 | 0.1793 | 0.1470
|
| 4096 | 125 | 0.2102 | 0.1565
|
| 8000 | 343 | 0.2014 | 0.1653
|
| 10648 | 512 | 0.2013 | 0.1544
|
- Run on MacBook? Pro (1.8 GHz Intel Core Duo).
| Number of Particles | Total Cells | Verlet List Timing | Verlet List w/Ghost Particles Timing
|
| 1000 | 27 | 0.1723 | 0.1070
|
| 2744 | 125 | 0.1397 | 0.1045
|
| 4096 | 125 | 0.1645 | 0.1168
|
Moderate Density LJ Fluid (rho=0.5), check every time, code revision 440
Brownian Dynamics LJ system with number density 0.5, T=1.0, and skin=0.375. The system checks every time step to see if a the neighborlist needs to be updated.
Timings are the number of seconds to run 10000 timesteps scaled by the number of particles.
- Run on AON (2.0 GHz Apple G5).
| Number of Particles | Total Cells | Verlet List Timing | Verlet List w/Ghost Particles Timing
|
| 1000 | 64 | 0.1078 | 0.1118
|
| 2744 | 216 | 0.1256 | 0.1158
|
| 4096 | 343 | 0.1330 | 0.1176
|
| 8000 | 512 | 0.1584 | 0.1305
|
| 10648 | 729 | 0.1647 | 0.1359
|
- Run on MacBook? Pro (1.8 GHz Intel Core Duo).
| Number of Particles | Total Cells | Verlet List Timing | Verlet List w/Ghost Particles Timing
|
| 1000 | 64 | 0.0924 | 0.0631
|
| 2744 | 216 | 0.0906 | 0.0710
|
| 4096 | 343 | 0.0907 | 0.0732
|
