Thanks Mark for your reply. For the time being, I admit your claim that I am comparing apple with orange. So, to investigate more, I run the simulation without any modification in parameter fields and force field I am using. My test data is CMV virus shell. I am using the following commands.
pdb2gmx -f 1F15-full.pdb -ter -ignh -ff amber99 -water none grompp -f mdr.mdp -c conf.gro -p topol.top -o imd.tpr OMP_NUM_THREADS=12 mdrun -nt 16 -s imd.tpr The log file looks like this: :-) G R O M A C S (-: GROningen MAchine for Chemical Simulation :-) VERSION 4.6-dev-20120820-87e5bcf (-: Written by Emile Apol, Rossen Apostolov, Herman J.C. Berendsen, Aldert van Buuren, Pär Bjelkmar, Rudi van Drunen, Anton Feenstra, Gerrit Groenhof, Peter Kasson, Per Larsson, Pieter Meulenhoff, Teemu Murtola, Szilard Pall, Sander Pronk, Roland Schulz, Michael Shirts, Alfons Sijbers, Peter Tieleman, Berk Hess, David van der Spoel, and Erik Lindahl. Copyright (c) 1991-2000, University of Groningen, The Netherlands. Copyright (c) 2001-2010, The GROMACS development team at Uppsala University & The Royal Institute of Technology, Sweden. check out http://www.gromacs.org for more information. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. :-) mdrun_mpi (-: ++++ PLEASE READ AND CITE THE FOLLOWING REFERENCE ++++ B. Hess and C. Kutzner and D. van der Spoel and E. Lindahl GROMACS 4: Algorithms for highly efficient, load-balanced, and scalable molecular simulation J. Chem. Theory Comput. 4 (2008) pp. 435-447 -------- -------- --- Thank You --- -------- -------- ++++ PLEASE READ AND CITE THE FOLLOWING REFERENCE ++++ D. van der Spoel, E. Lindahl, B. Hess, G. Groenhof, A. E. Mark and H. J. C. Berendsen GROMACS: Fast, Flexible and Free J. Comp. Chem. 26 (2005) pp. 1701-1719 -------- -------- --- Thank You --- -------- -------- ++++ PLEASE READ AND CITE THE FOLLOWING REFERENCE ++++ E. Lindahl and B. Hess and D. van der Spoel GROMACS 3.0: A package for molecular simulation and trajectory analysis J. Mol. Mod. 7 (2001) pp. 306-317 -------- -------- --- Thank You --- -------- -------- ++++ PLEASE READ AND CITE THE FOLLOWING REFERENCE ++++ H. J. C. Berendsen, D. van der Spoel and R. van Drunen GROMACS: A message-passing parallel molecular dynamics implementation Comp. Phys. Comm. 91 (1995) pp. 43-56 -------- -------- --- Thank You --- -------- -------- Input Parameters: integrator = md nsteps = 0 init-step = 0 ns-type = Grid nstlist = 10 ndelta = 2 nstcomm = 10 comm-mode = Linear nstlog = 1000 nstxout = 0 nstvout = 0 nstfout = 0 nstcalcenergy = 10 nstenergy = 100 nstxtcout = 0 init-t = 0 delta-t = 0.001 xtcprec = 1000 nkx = 0 nky = 0 nkz = 0 pme-order = 4 ewald-rtol = 1e-05 ewald-geometry = 0 epsilon-surface = 0 optimize-fft = FALSE ePBC = no bPeriodicMols = FALSE bContinuation = FALSE bShakeSOR = FALSE etc = No bPrintNHChains = FALSE nsttcouple = -1 epc = No epctype = Isotropic nstpcouple = -1 tau-p = 1 ref-p (3x3): ref-p[ 0]={ 0.00000e+00, 0.00000e+00, 0.00000e+00} ref-p[ 1]={ 0.00000e+00, 0.00000e+00, 0.00000e+00} ref-p[ 2]={ 0.00000e+00, 0.00000e+00, 0.00000e+00} compress (3x3): compress[ 0]={ 0.00000e+00, 0.00000e+00, 0.00000e+00} compress[ 1]={ 0.00000e+00, 0.00000e+00, 0.00000e+00} compress[ 2]={ 0.00000e+00, 0.00000e+00, 0.00000e+00} refcoord-scaling = No posres-com (3): posres-com[0]= 0.00000e+00 posres-com[1]= 0.00000e+00 posres-com[2]= 0.00000e+00 posres-comB (3): posres-comB[0]= 0.00000e+00 posres-comB[1]= 0.00000e+00 posres-comB[2]= 0.00000e+00 rlist = 1 rlistlong = 1 rtpi = 0.05 coulombtype = Cut-off rcoulomb-switch = 0 rcoulomb = 1 vdwtype = Cut-off rvdw-switch = 0 rvdw = 1 epsilon-r = 1 epsilon-rf = inf tabext = 1 implicit-solvent = GBSA gb-algorithm = HCT gb-epsilon-solvent = 80 nstgbradii = 1 rgbradii = 1 gb-saltconc = 0 gb-obc-alpha = 1 gb-obc-beta = 0.8 gb-obc-gamma = 4.85 gb-dielectric-offset = 0.009 sa-algorithm = None sa-surface-tension = 2.25936 DispCorr = No bSimTemp = FALSE free-energy = no nwall = 0 wall-type = 9-3 wall-atomtype[0] = -1 wall-atomtype[1] = -1 wall-density[0] = 0 wall-density[1] = 0 wall-ewald-zfac = 3 pull = no rotation = FALSE disre = No disre-weighting = Conservative disre-mixed = FALSE dr-fc = 1000 dr-tau = 0 nstdisreout = 100 orires-fc = 0 orires-tau = 0 nstorireout = 100 dihre-fc = 0 em-stepsize = 0.01 em-tol = 10 niter = 20 fc-stepsize = 0 nstcgsteep = 1000 nbfgscorr = 10 ConstAlg = Lincs shake-tol = 0.0001 lincs-order = 4 lincs-warnangle = 30 lincs-iter = 1 bd-fric = 0 ld-seed = 1993 cos-accel = 0 deform (3x3): deform[ 0]={ 0.00000e+00, 0.00000e+00, 0.00000e+00} deform[ 1]={ 0.00000e+00, 0.00000e+00, 0.00000e+00} deform[ 2]={ 0.00000e+00, 0.00000e+00, 0.00000e+00} adress = FALSE userint1 = 0 userint2 = 0 userint3 = 0 userint4 = 0 userreal1 = 0 userreal2 = 0 userreal3 = 0 userreal4 = 0 grpopts: nrdf: 9534 ref-t: 0 tau-t: 0 anneal: No ann-npoints: 0 acc: 0 0 0 nfreeze: N N N energygrp-flags[ 0]: 0 efield-x: n = 0 efield-xt: n = 0 efield-y: n = 0 efield-yt: n = 0 efield-z: n = 0 efield-zt: n = 0 bQMMM = FALSE QMconstraints = 0 QMMMscheme = 0 scalefactor = 1 qm-opts: ngQM = 0 Initializing Domain Decomposition on 16 nodes Dynamic load balancing: auto Will sort the charge groups at every domain (re)decomposition Minimum cell size due to bonded interactions: 0.000 nm Scaling the initial minimum size with 1/0.8 (option -dds) = 1.25 Optimizing the DD grid for 16 cells with a minimum initial size of 0.000 nm Domain decomposition grid 4 x 4 x 1, separate PME nodes 0 Domain decomposition nodeid 0, coordinates 0 0 0 Detecting CPU-specific acceleration. Present hardware specification: Vendor: GenuineIntel Brand: Intel(R) Xeon(R) CPU X5680 @ 3.33GHz Family: 6 Model: 44 Stepping: 2 Features: htt sse2 sse4.1 aes rdtscp Acceleration most likely to fit this hardware: SSE4.1 Acceleration selected at Gromacs compile time: SSE4.1 Table routines are used for coulomb: FALSE Table routines are used for vdw: FALSE Cut-off's: NS: 1 Coulomb: 1 LJ: 1 System total charge: 6.000 Configuring nonbonded kernels... Configuring standard C nonbonded kernels... Linking all bonded interactions to atoms The initial number of communication pulses is: X 2 Y 2 The initial domain decomposition cell size is: X 0.79 nm Y 0.89 nm The maximum allowed distance for charge groups involved in interactions is: non-bonded interactions 1.000 nm (the following are initial values, they could change due to box deformation) two-body bonded interactions (-rdd) 1.000 nm multi-body bonded interactions (-rdd) 0.794 nm When dynamic load balancing gets turned on, these settings will change to: The maximum number of communication pulses is: X 2 Y 2 The minimum size for domain decomposition cells is 0.500 nm The requested allowed shrink of DD cells (option -dds) is: 0.80 The allowed shrink of domain decomposition cells is: X 0.63 Y 0.56 The maximum allowed distance for charge groups involved in interactions is: non-bonded interactions 1.000 nm two-body bonded interactions (-rdd) 1.000 nm multi-body bonded interactions (-rdd) 0.500 nm Making 2D domain decomposition grid 4 x 4 x 1, home cell index 0 0 0 Center of mass motion removal mode is Linear We have the following groups for center of mass motion removal: 0: rest There are: 3179 Atoms Charge group distribution at step 0: 84 180 252 196 237 210 255 157 254 197 266 176 186 104 224 201 Grid: 4 x 4 x 4 cells Initial temperature: 0 K Started mdrun on node 0 Wed Aug 29 02:32:21 2012 Step Time Lambda 0 0.00000 0.00000 Energies (kJ/mol) GB Polarization LJ (SR) Coulomb (SR) Potential Kinetic En. -1.65116e+04 5.74908e+08 -2.37699e+05 5.74654e+08 6.36009e+11 Total Energy Temperature Pressure (bar) 6.36584e+11 1.60465e+10 0.00000e+00 <====== ############### ==> <==== A V E R A G E S ====> <== ############### ======> Statistics over 1 steps using 1 frames Energies (kJ/mol) GB Polarization LJ (SR) Coulomb (SR) Potential Kinetic En. -1.65116e+04 5.74908e+08 -2.37699e+05 5.74654e+08 6.36009e+11 Total Energy Temperature Pressure (bar) 6.36584e+11 1.60465e+10 0.00000e+00 Total Virial (kJ/mol) -1.13687e+09 1.14300e+07 -1.23884e+07 1.14273e+07 -1.15125e+09 -5.31658e+06 -1.23830e+07 -5.31326e+06 -1.16512e+09 Pressure (bar) 0.00000e+00 0.00000e+00 0.00000e+00 0.00000e+00 0.00000e+00 0.00000e+00 0.00000e+00 0.00000e+00 0.00000e+00 Total Dipole (D) 1.35524e+03 -4.39059e+01 2.16985e+03 M E G A - F L O P S A C C O U N T I N G RF=Reaction-Field FE=Free Energy SCFE=Soft-Core/Free Energy T=Tabulated W3=SPC/TIP3p W4=TIP4p (single or pairs) NF=No Forces Computing: M-Number M-Flops % Flops ----------------------------------------------------------------------------- Generalized Born Coulomb 0.006162 0.296 0.2 GB Coulomb + LJ 0.446368 27.228 19.8 Outer nonbonded loop 0.015554 0.156 0.1 Born radii (HCT/OBC) 0.452530 82.813 60.3 Born force chain rule 0.452530 6.788 4.9 NS-Pairs 0.940291 19.746 14.4 Reset In Box 0.003179 0.010 0.0 CG-CoM 0.006358 0.019 0.0 Virial 0.003899 0.070 0.1 Stop-CM 0.006358 0.064 0.0 Calc-Ekin 0.006358 0.172 0.1 ----------------------------------------------------------------------------- Total 137.361 100.0 ----------------------------------------------------------------------------- D O M A I N D E C O M P O S I T I O N S T A T I S T I C S av. #atoms communicated per step for force: 2 x 7369.0 R E A L C Y C L E A N D T I M E A C C O U N T I N G Computing: Nodes Number G-Cycles Seconds % ----------------------------------------------------------------------- Domain decomp. 16 1 0.210 0.1 11.4 Comm. coord. 16 1 0.006 0.0 0.3 Neighbor search 16 1 0.118 0.1 6.4 Force 16 1 1.319 0.8 71.4 Wait + Comm. F 16 1 0.016 0.0 0.9 Update 16 1 0.003 0.0 0.2 Comm. energies 16 1 0.093 0.1 5.0 Rest 16 0.082 0.1 4.4 ----------------------------------------------------------------------- Total 16 1.847 1.1 100.0 ----------------------------------------------------------------------- NOTE: 5 % of the run time was spent communicating energies, you might want to use the -gcom option of mdrun Parallel run - timing based on wallclock. NODE (s) Real (s) (%) Time: 0.036 0.036 100.0 (Mnbf/s) (GFlops) (ns/day) (hour/ns) Performance: 12.702 3.856 2.425 9.896 Finished mdrun on node 0 Wed Aug 29 02:32:21 2012 The GB- energy value reported is half of that reported by Amber 11 and Octree based Molecular dynamic package. Although I guess the difference can be due to the difference in algorithms they are using, but there could be some other reason. If anyone knows what are the possible reasons behind this, please let me know. May be fixing them will give me same value for all different Molecular Dynamic Package. Best Regard, Jesmin On Mon, Aug 27, 2012 at 6:25 PM, Mark Abraham <mark.abra...@anu.edu.au> wrote: > On 28/08/2012 2:33 AM, jesmin jahan wrote: >> >> Dear All, >> >> I am using Gromacs 4.5.3 for GB-Polarization Energy Calculation. As I >> am not interested to any other energy terms right now, I have set all >> the non-bonded parameters to 0. >> >> I am also calculating GB polarization energy using other available >> Molecular Dynamic Packages and doing a comparative study between them >> (say: Accuracy Vs. Speed Up). >> I have already used Gromacs for calculating GB-energy for 168 >> different Protein molecules and the energy values reported were more >> or less the same as reported by others. >> >> Now, I am using a virus shell as input in this process. It contains >> 1.5 million atoms. Unfortunately, this time, the energy reported is >> almost half of the value reported by others. >> So, I am a little bit confused. Am I doing something wrong? I have >> heard previously that there is no max size for Gromacs. > > > Probably you're comparing apples with oranges. Your previous reports were > choosing to use a cut-off in the non-bonded interactions. Perhaps some of > the other codes are not or cannot. That would greatly affect performance and > the value of the result, and is part of why it is meaningless to try to > extract the time for just a part of a calculation without the timing of its > support infrastructure (such as constructing the pair list from the > cut-off). Also, since you are computing on proteins, you probably have > bonded and VDW interactions in your force field also, and your timing > comparisons will be misleading if you ignore those. The time taken to > execute an implementation of a complex algorithm is rarely additive in its > parts. For example, software that makes good or bad use of the cache in a > real calculation won't have the opportunity to show that if the whole > problem size fits in the L1 cache because it's been stripped down. > > Mark > -- > gmx-users mailing list gmx-users@gromacs.org > http://lists.gromacs.org/mailman/listinfo/gmx-users > * Please search the archive at > http://www.gromacs.org/Support/Mailing_Lists/Search before posting! > * Please don't post (un)subscribe requests to the list. Use the www > interface or send it to gmx-users-requ...@gromacs.org. > * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists -- Jesmin Jahan Tithi PhD Student, CS Stony Brook University, NY-11790. -- gmx-users mailing list gmx-users@gromacs.org http://lists.gromacs.org/mailman/listinfo/gmx-users * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/Search before posting! * Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org. * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists