LAMMPS-ICMS version 19 Nov 2010

Here as some simple comparisons (note the different number of CPU cores) with results from lammps-icms binaries compiled for various machines on the NSF TeraGrid. This is mainly to give an orientation to see what kind of performance can be expected from using hybrid OpenMP/MPI or GPU/MPI parallel execution of LAMMPS. The input files and raw output can be retrieved from
the LAMMPS-ICMS git repository.

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Machine
- NICS Kraken: Cray XT5, 2x 2.6 GHz 6-core AMD Opteron per node, SeaStar2
- TACC Ranger: Sun Constellation, 4x 2.3 GHz 4-core AMD Opteron per node, SDR Infiniband
- NCSA Abe: Dell Blade Cluster, 2x 2.33 GHz 4-core Intel Xeon (Clovertown), DDR Infiniband
- TACC Longhorn: Dell r610 Cluster, 2x 2.53 GHz 4-core Intel Xeon (Nehalem), 2x Nvidia Quadro FX 5800, QDR Infiniband

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Test system 1: Lennard-Jones melt: 1,149,984 particles for 10,000 MD steps

Machine	Nodes	MPI tasks	OpenMP/MPI	GPU/MPI	Time/s
NICS Kraken	32	384	-	-	72.8
NICS Kraken	32	192	2	-	72.6
NICS Kraken	32	128	3	-	79.4
NICS Kraken	32	64	6	-	102.7
TACC Ranger	8	128	-	-	230.0
TACC Ranger	8	64	2	-	215.3
TACC Ranger	8	32	4	-	305.7
TACC Longhorn	16	128	-	-	103.0
TACC Longhorn	16	64	2	-	110.5
TACC Longhorn	16	32	-	1	51.9
NCSA Abe	16	112	-	-	193.9
NCSA Abe	16	64	2	-	201.1
NCSA Lincoln	16	32	-	1	74.7

Test system 2: Gay-Berne droplet: 64,000 particles for 10,000 MD steps

Machine	Nodes	MPI tasks	OpenMP/MPI	GPU/MPI	Time/s
NICS Kraken	16	192	-	-	738.9
NICS Kraken	16	96	2	-	746.2
NICS Kraken	16	64	3	-	731.9
NICS Kraken	16	32	6	-	752.1
TACC Ranger	8	128	-	-	905.8
TACC Ranger	8	64	2	-	917.1
TACC Ranger	8	32	4	-	909.1
TACC Longhorn	16	128	-	-	510.1
TACC Longhorn	16	32	4	-	508.4
TACC Longhorn	16	32	-	1	93.4
NCSA Abe	16	112	-	-	1042.3
NCSA Abe	16	64	2	-	921.3

Test system 3: SDS coarse grain monolayer: 250,240 particles for 10,000 MD steps

Machine	Nodes	MPI tasks	OpenMP/MPI	GPU/MPI	Time/s
NICS Kraken	8	96	-	-	254.0
NICS Kraken	8	48	2	-	230.9
NICS Kraken	8	32	3	-	248.9
NICS Kraken	8	16	6	-	344.9
TACC Ranger	8	128	-	-	294.7
TACC Ranger	8	64	2	-	193.5
TACC Ranger	8	32	4	-	262.0
TACC Longhorn	16	128	-	-	125.2
TACC Longhorn	16	64	2	-	108.3
TACC Longhorn	16	32	-	1	43.7
NCSA Abe	16	112	-	-	212.3
NCSA Abe	16	64	2	-	171.3

Test system 4: Bulk CHARMM water : 84,000 atoms for 10,000 MD steps

Machine	Nodes	MPI tasks	OpenMP/MPI	GPU/MPI	Time/s
NICS Kraken	16	192	-	-	430.7
NICS Kraken	16	96	2	-	347.8
NICS Kraken	16	64	3	-	348.8
NICS Kraken	16	32	6	-	508.1
TACC Ranger	8	128	-	-	681.7
TACC Ranger	8	64	2	-	547.3
TACC Ranger	8	32	4	-	668.0
TACC Longhorn	16	128	-	-	323.9
TACC Longhorn	16	64	2	-	298.6
TACC Longhorn	16	32	-	1	211.1
NCSA Abe	16	112	-	-	527.1
NCSA Abe	16	64	2	-	430.3