diff --git a/src/balance.cpp b/src/balance.cpp index c184a72d3..8f994466a 100644 --- a/src/balance.cpp +++ b/src/balance.cpp @@ -1,1337 +1,1337 @@ /* ---------------------------------------------------------------------- LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator http://lammps.sandia.gov, Sandia National Laboratories Steve Plimpton, sjplimp@sandia.gov Copyright (2003) Sandia Corporation. Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains certain rights in this software. This software is distributed under the GNU General Public License. See the README file in the top-level LAMMPS directory. ------------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- Contributing authors, for weighted balancing: Axel Kohlmeyer (Temple U), Iain Bethune (EPCC) ------------------------------------------------------------------------- */ //#define BALANCE_DEBUG 1 #include #include #include #include #include "balance.h" #include "atom.h" #include "comm.h" #include "rcb.h" #include "irregular.h" #include "domain.h" #include "force.h" #include "update.h" #include "group.h" #include "modify.h" #include "fix_store.h" #include "imbalance.h" #include "imbalance_group.h" #include "imbalance_time.h" #include "imbalance_neigh.h" #include "imbalance_store.h" #include "imbalance_var.h" #include "timer.h" #include "memory.h" #include "error.h" using namespace LAMMPS_NS; enum{XYZ,SHIFT,BISECTION}; enum{NONE,UNIFORM,USER}; enum{X,Y,Z}; enum{LAYOUT_UNIFORM,LAYOUT_NONUNIFORM,LAYOUT_TILED}; // several files /* ---------------------------------------------------------------------- */ Balance::Balance(LAMMPS *lmp) : Pointers(lmp) { MPI_Comm_rank(world,&me); MPI_Comm_size(world,&nprocs); user_xsplit = user_ysplit = user_zsplit = NULL; shift_allocate = 0; proccost = allproccost = NULL; rcb = NULL; nimbalance = 0; imbalances = NULL; fixstore = NULL; fp = NULL; firststep = 1; } /* ---------------------------------------------------------------------- */ Balance::~Balance() { memory->destroy(proccost); memory->destroy(allproccost); delete [] user_xsplit; delete [] user_ysplit; delete [] user_zsplit; if (shift_allocate) { delete [] bdim; delete [] onecost; delete [] allcost; delete [] sum; delete [] target; delete [] lo; delete [] hi; delete [] losum; delete [] hisum; } delete rcb; for (int i = 0; i < nimbalance; i++) delete imbalances[i]; delete [] imbalances; // check nfix in case all fixes have already been deleted if (fixstore && modify->nfix) modify->delete_fix(fixstore->id); fixstore = NULL; if (fp) fclose(fp); } /* ---------------------------------------------------------------------- called as balance command in input script ------------------------------------------------------------------------- */ void Balance::command(int narg, char **arg) { if (domain->box_exist == 0) error->all(FLERR,"Balance command before simulation box is defined"); if (me == 0 && screen) fprintf(screen,"Balancing ...\n"); // parse required arguments if (narg < 2) error->all(FLERR,"Illegal balance command"); thresh = force->numeric(FLERR,arg[0]); int dimension = domain->dimension; int *procgrid = comm->procgrid; style = -1; xflag = yflag = zflag = NONE; int iarg = 1; while (iarg < narg) { if (strcmp(arg[iarg],"x") == 0) { if (style != -1 && style != XYZ) error->all(FLERR,"Illegal balance command"); style = XYZ; if (strcmp(arg[iarg+1],"uniform") == 0) { if (iarg+2 > narg) error->all(FLERR,"Illegal balance command"); xflag = UNIFORM; iarg += 2; } else { if (1 + procgrid[0]-1 > narg) error->all(FLERR,"Illegal balance command"); xflag = USER; delete [] user_xsplit; user_xsplit = new double[procgrid[0]+1]; user_xsplit[0] = 0.0; iarg++; for (int i = 1; i < procgrid[0]; i++) user_xsplit[i] = force->numeric(FLERR,arg[iarg++]); user_xsplit[procgrid[0]] = 1.0; } } else if (strcmp(arg[iarg],"y") == 0) { if (style != -1 && style != XYZ) error->all(FLERR,"Illegal balance command"); style = XYZ; if (strcmp(arg[iarg+1],"uniform") == 0) { if (iarg+2 > narg) error->all(FLERR,"Illegal balance command"); yflag = UNIFORM; iarg += 2; } else { if (1 + procgrid[1]-1 > narg) error->all(FLERR,"Illegal balance command"); yflag = USER; delete [] user_ysplit; user_ysplit = new double[procgrid[1]+1]; user_ysplit[0] = 0.0; iarg++; for (int i = 1; i < procgrid[1]; i++) user_ysplit[i] = force->numeric(FLERR,arg[iarg++]); user_ysplit[procgrid[1]] = 1.0; } } else if (strcmp(arg[iarg],"z") == 0) { if (style != -1 && style != XYZ) error->all(FLERR,"Illegal balance command"); style = XYZ; if (strcmp(arg[iarg+1],"uniform") == 0) { if (iarg+2 > narg) error->all(FLERR,"Illegal balance command"); zflag = UNIFORM; iarg += 2; } else { if (1 + procgrid[2]-1 > narg) error->all(FLERR,"Illegal balance command"); zflag = USER; delete [] user_zsplit; user_zsplit = new double[procgrid[2]+1]; user_zsplit[0] = 0.0; iarg++; for (int i = 1; i < procgrid[2]; i++) user_zsplit[i] = force->numeric(FLERR,arg[iarg++]); user_zsplit[procgrid[2]] = 1.0; } } else if (strcmp(arg[iarg],"shift") == 0) { if (style != -1) error->all(FLERR,"Illegal balance command"); if (iarg+4 > narg) error->all(FLERR,"Illegal balance command"); style = SHIFT; if (strlen(arg[iarg+1]) > 3) error->all(FLERR,"Illegal balance command"); strcpy(bstr,arg[iarg+1]); nitermax = force->inumeric(FLERR,arg[iarg+2]); if (nitermax <= 0) error->all(FLERR,"Illegal balance command"); stopthresh = force->numeric(FLERR,arg[iarg+3]); if (stopthresh < 1.0) error->all(FLERR,"Illegal balance command"); iarg += 4; } else if (strcmp(arg[iarg],"rcb") == 0) { if (style != -1) error->all(FLERR,"Illegal balance command"); style = BISECTION; iarg++; } else break; } // error checks if (style == XYZ) { if (zflag != NONE && dimension == 2) error->all(FLERR,"Cannot balance in z dimension for 2d simulation"); if (xflag == USER) for (int i = 1; i <= procgrid[0]; i++) if (user_xsplit[i-1] >= user_xsplit[i]) error->all(FLERR,"Illegal balance command"); if (yflag == USER) for (int i = 1; i <= procgrid[1]; i++) if (user_ysplit[i-1] >= user_ysplit[i]) error->all(FLERR,"Illegal balance command"); if (zflag == USER) for (int i = 1; i <= procgrid[2]; i++) if (user_zsplit[i-1] >= user_zsplit[i]) error->all(FLERR,"Illegal balance command"); } if (style == SHIFT) { const int blen=strlen(bstr); for (int i = 0; i < blen; i++) { if (bstr[i] != 'x' && bstr[i] != 'y' && bstr[i] != 'z') error->all(FLERR,"Balance shift string is invalid"); if (bstr[i] == 'z' && dimension == 2) error->all(FLERR,"Balance shift string is invalid"); for (int j = i+1; j < blen; j++) if (bstr[i] == bstr[j]) error->all(FLERR,"Balance shift string is invalid"); } } if (style == BISECTION && comm->style == 0) error->all(FLERR,"Balance rcb cannot be used with comm_style brick"); // process remaining optional args options(iarg,narg,arg); if (wtflag) weight_storage(NULL); // insure particles are in current box & update box via shrink-wrap // init entire system since comm->setup is done // comm::init needs neighbor::init needs pair::init needs kspace::init, etc // must reset atom map after exchange() since it clears it MPI_Barrier(world); double start_time = MPI_Wtime(); lmp->init(); if (domain->triclinic) domain->x2lamda(atom->nlocal); domain->pbc(); domain->reset_box(); comm->setup(); comm->exchange(); if (atom->map_style) atom->map_set(); if (domain->triclinic) domain->lamda2x(atom->nlocal); // imbinit = initial imbalance double maxinit; init_imbalance(0); set_weights(); double imbinit = imbalance_factor(maxinit); // no load-balance if imbalance doesn't exceed threshold // unless switching from tiled to non tiled layout, then force rebalance if (comm->layout == LAYOUT_TILED && style != BISECTION) { } else if (imbinit < thresh) return; // debug output of initial state #ifdef BALANCE_DEBUG if (outflag) dumpout(update->ntimestep); #endif int niter = 0; // perform load-balance // style XYZ = explicit setting of cutting planes of logical 3d grid if (style == XYZ) { if (comm->layout == LAYOUT_UNIFORM) { if (xflag == USER || yflag == USER || zflag == USER) comm->layout = LAYOUT_NONUNIFORM; } else if (comm->style == LAYOUT_NONUNIFORM) { if (xflag == UNIFORM && yflag == UNIFORM && zflag == UNIFORM) comm->layout = LAYOUT_UNIFORM; } else if (comm->style == LAYOUT_TILED) { if (xflag == UNIFORM && yflag == UNIFORM && zflag == UNIFORM) comm->layout = LAYOUT_UNIFORM; else comm->layout = LAYOUT_NONUNIFORM; } if (xflag == UNIFORM) { for (int i = 0; i < procgrid[0]; i++) comm->xsplit[i] = i * 1.0/procgrid[0]; comm->xsplit[procgrid[0]] = 1.0; } else if (xflag == USER) for (int i = 0; i <= procgrid[0]; i++) comm->xsplit[i] = user_xsplit[i]; if (yflag == UNIFORM) { for (int i = 0; i < procgrid[1]; i++) comm->ysplit[i] = i * 1.0/procgrid[1]; comm->ysplit[procgrid[1]] = 1.0; } else if (yflag == USER) for (int i = 0; i <= procgrid[1]; i++) comm->ysplit[i] = user_ysplit[i]; if (zflag == UNIFORM) { for (int i = 0; i < procgrid[2]; i++) comm->zsplit[i] = i * 1.0/procgrid[2]; comm->zsplit[procgrid[2]] = 1.0; } else if (zflag == USER) for (int i = 0; i <= procgrid[2]; i++) comm->zsplit[i] = user_zsplit[i]; } // style SHIFT = adjust cutting planes of logical 3d grid if (style == SHIFT) { comm->layout = LAYOUT_NONUNIFORM; shift_setup_static(bstr); niter = shift(); } // style BISECTION = recursive coordinate bisectioning if (style == BISECTION) { comm->layout = LAYOUT_TILED; bisection(1); } // reset proc sub-domains // for either brick or tiled comm style if (domain->triclinic) domain->set_lamda_box(); domain->set_local_box(); // move particles to new processors via irregular() if (domain->triclinic) domain->x2lamda(atom->nlocal); Irregular *irregular = new Irregular(lmp); if (wtflag) fixstore->disable = 0; if (style == BISECTION) irregular->migrate_atoms(1,1,rcb->sendproc); else irregular->migrate_atoms(1); if (wtflag) fixstore->disable = 1; delete irregular; if (domain->triclinic) domain->lamda2x(atom->nlocal); // output of final result if (outflag) dumpout(update->ntimestep); // check if any particles were lost bigint natoms; bigint nblocal = atom->nlocal; MPI_Allreduce(&nblocal,&natoms,1,MPI_LMP_BIGINT,MPI_SUM,world); if (natoms != atom->natoms) { char str[128]; sprintf(str,"Lost atoms via balance: original " BIGINT_FORMAT " current " BIGINT_FORMAT,atom->natoms,natoms); error->all(FLERR,str); } // imbfinal = final imbalance double maxfinal; double imbfinal = imbalance_factor(maxfinal); // stats output double stop_time = MPI_Wtime(); if (me == 0) { if (screen) { fprintf(screen," rebalancing time: %g seconds\n",stop_time-start_time); fprintf(screen," iteration count = %d\n",niter); for (int i = 0; i < nimbalance; ++i) imbalances[i]->info(screen); fprintf(screen," initial/final max load/proc = %g %g\n", maxinit,maxfinal); fprintf(screen," initial/final imbalance factor = %g %g\n", imbinit,imbfinal); } if (logfile) { fprintf(logfile," rebalancing time: %g seconds\n",stop_time-start_time); fprintf(logfile," iteration count = %d\n",niter); for (int i = 0; i < nimbalance; ++i) imbalances[i]->info(logfile); fprintf(logfile," initial/final max load/proc = %g %g\n", maxinit,maxfinal); fprintf(logfile," initial/final imbalance factor = %g %g\n", imbinit,imbfinal); } } if (style != BISECTION) { if (me == 0) { if (screen) { fprintf(screen," x cuts:"); for (int i = 0; i <= comm->procgrid[0]; i++) fprintf(screen," %g",comm->xsplit[i]); fprintf(screen,"\n"); fprintf(screen," y cuts:"); for (int i = 0; i <= comm->procgrid[1]; i++) fprintf(screen," %g",comm->ysplit[i]); fprintf(screen,"\n"); fprintf(screen," z cuts:"); for (int i = 0; i <= comm->procgrid[2]; i++) fprintf(screen," %g",comm->zsplit[i]); fprintf(screen,"\n"); } if (logfile) { fprintf(logfile," x cuts:"); for (int i = 0; i <= comm->procgrid[0]; i++) fprintf(logfile," %g",comm->xsplit[i]); fprintf(logfile,"\n"); fprintf(logfile," y cuts:"); for (int i = 0; i <= comm->procgrid[1]; i++) fprintf(logfile," %g",comm->ysplit[i]); fprintf(logfile,"\n"); fprintf(logfile," z cuts:"); for (int i = 0; i <= comm->procgrid[2]; i++) fprintf(logfile," %g",comm->zsplit[i]); fprintf(logfile,"\n"); } } } } /* ---------------------------------------------------------------------- process optional command args for Balance and FixBalance ------------------------------------------------------------------------- */ void Balance::options(int iarg, int narg, char **arg) { // count max number of weight settings nimbalance = 0; for (int i = iarg; i < narg; i++) if (strcmp(arg[i],"weight") == 0) nimbalance++; if (nimbalance) imbalances = new Imbalance*[nimbalance]; nimbalance = 0; wtflag = 0; varflag = 0; oldrcb = 0; outflag = 0; int outarg = 0; fp = NULL; while (iarg < narg) { if (strcmp(arg[iarg],"weight") == 0) { wtflag = 1; Imbalance *imb; int nopt = 0; if (strcmp(arg[iarg+1],"group") == 0) { imb = new ImbalanceGroup(lmp); nopt = imb->options(narg-iarg,arg+iarg+2); imbalances[nimbalance++] = imb; } else if (strcmp(arg[iarg+1],"time") == 0) { imb = new ImbalanceTime(lmp); nopt = imb->options(narg-iarg,arg+iarg+2); imbalances[nimbalance++] = imb; } else if (strcmp(arg[iarg+1],"neigh") == 0) { imb = new ImbalanceNeigh(lmp); nopt = imb->options(narg-iarg,arg+iarg+2); imbalances[nimbalance++] = imb; } else if (strcmp(arg[iarg+1],"var") == 0) { varflag = 1; imb = new ImbalanceVar(lmp); nopt = imb->options(narg-iarg,arg+iarg+2); imbalances[nimbalance++] = imb; } else if (strcmp(arg[iarg+1],"store") == 0) { imb = new ImbalanceStore(lmp); nopt = imb->options(narg-iarg,arg+iarg+2); imbalances[nimbalance++] = imb; } else { error->all(FLERR,"Unknown (fix) balance weight method"); } iarg += 2+nopt; } else if (strcmp(arg[iarg],"old") == 0) { oldrcb = 1; iarg++; } else if (strcmp(arg[iarg],"out") == 0) { if (iarg+2 > narg) error->all(FLERR,"Illegal (fix) balance command"); outflag = 1; outarg = iarg+1; iarg += 2; } else error->all(FLERR,"Illegal (fix) balance command"); } // output file if (outflag && comm->me == 0) { fp = fopen(arg[outarg],"w"); if (fp == NULL) error->one(FLERR,"Cannot open (fix) balance output file"); } } /* ---------------------------------------------------------------------- allocate per-particle weight storage via FixStore use prefix to distinguish Balance vs FixBalance storage fix could already be allocated if fix balance is re-specified ------------------------------------------------------------------------- */ void Balance::weight_storage(char *prefix) { char *fixargs[6]; if (prefix) { int n = strlen(prefix) + 32; fixargs[0] = new char[n]; strcpy(fixargs[0],prefix); strcat(fixargs[0],"IMBALANCE_WEIGHTS"); } else fixargs[0] = (char *) "IMBALANCE_WEIGHTS"; fixargs[1] = (char *) "all"; fixargs[2] = (char *) "STORE"; fixargs[3] = (char *) "peratom"; fixargs[4] = (char *) "0"; fixargs[5] = (char *) "1"; int ifix = modify->find_fix(fixargs[0]); if (ifix < 1) { modify->add_fix(6,fixargs); fixstore = (FixStore *) modify->fix[modify->nfix-1]; } else fixstore = (FixStore *) modify->fix[ifix]; fixstore->disable = 1; if (prefix) delete [] fixargs[0]; } /* ---------------------------------------------------------------------- invoke init() for each Imbalance class flag = 0 for call from Balance, 1 for call from FixBalance ------------------------------------------------------------------------- */ void Balance::init_imbalance(int flag) { if (!wtflag) return; for (int n = 0; n < nimbalance; n++) imbalances[n]->init(flag); } /* ---------------------------------------------------------------------- set weight for each particle via list of Nimbalance classes ------------------------------------------------------------------------- */ void Balance::set_weights() { if (!wtflag) return; weight = fixstore->vstore; int nlocal = atom->nlocal; for (int i = 0; i < nlocal; i++) weight[i] = 1.0; for (int n = 0; n < nimbalance; n++) imbalances[n]->compute(weight); } /* ---------------------------------------------------------------------- calculate imbalance factor based on particle count or particle weights return max = max load per proc return imbalance = max load per proc / ave load per proc ------------------------------------------------------------------------- */ double Balance::imbalance_factor(double &maxcost) { double mycost,totalcost; if (wtflag) { weight = fixstore->vstore; int nlocal = atom->nlocal; mycost = 0.0; for (int i = 0; i < nlocal; i++) mycost += weight[i]; } else mycost = atom->nlocal; MPI_Allreduce(&mycost,&maxcost,1,MPI_DOUBLE,MPI_MAX,world); MPI_Allreduce(&mycost,&totalcost,1,MPI_DOUBLE,MPI_SUM,world); double imbalance = 1.0; if (maxcost > 0.0) imbalance = maxcost / (totalcost/nprocs); return imbalance; } /* ---------------------------------------------------------------------- perform balancing via RCB class sortflag = flag for sorting order of received messages by proc ID return list of procs to send my atoms to ------------------------------------------------------------------------- */ int *Balance::bisection(int sortflag) { if (!rcb) rcb = new RCB(lmp); // NOTE: this logic is specific to orthogonal boxes, not triclinic int dim = domain->dimension; double *boxlo = domain->boxlo; double *boxhi = domain->boxhi; double *prd = domain->prd; // shrink-wrap simulation box around atoms for input to RCB // leads to better-shaped sub-boxes when atoms are far from box boundaries double shrink[6],shrinkall[6]; shrink[0] = boxhi[0]; shrink[1] = boxhi[1]; shrink[2] = boxhi[2]; shrink[3] = boxlo[0]; shrink[4] = boxlo[1]; shrink[5] = boxlo[2]; double **x = atom->x; int nlocal = atom->nlocal; for (int i = 0; i < nlocal; i++) { shrink[0] = MIN(shrink[0],x[i][0]); shrink[1] = MIN(shrink[1],x[i][1]); shrink[2] = MIN(shrink[2],x[i][2]); shrink[3] = MAX(shrink[3],x[i][0]); shrink[4] = MAX(shrink[4],x[i][1]); shrink[5] = MAX(shrink[5],x[i][2]); } shrink[3] = -shrink[3]; shrink[4] = -shrink[4]; shrink[5] = -shrink[5]; MPI_Allreduce(shrink,shrinkall,6,MPI_DOUBLE,MPI_MIN,world); shrinkall[3] = -shrinkall[3]; shrinkall[4] = -shrinkall[4]; shrinkall[5] = -shrinkall[5]; double *shrinklo = &shrinkall[0]; double *shrinkhi = &shrinkall[3]; // invoke RCB // then invert() to create list of proc assignments for my atoms // NOTE: (3/2017) can remove undocumented "old" option at some point // ditto in rcb.cpp if (oldrcb) { if (wtflag) { weight = fixstore->vstore; rcb->compute_old(dim,atom->nlocal,atom->x,weight,shrinklo,shrinkhi); } else rcb->compute_old(dim,atom->nlocal,atom->x,NULL,shrinklo,shrinkhi); } else { if (wtflag) { weight = fixstore->vstore; rcb->compute(dim,atom->nlocal,atom->x,weight,shrinklo,shrinkhi); } else rcb->compute(dim,atom->nlocal,atom->x,NULL,shrinklo,shrinkhi); } rcb->invert(sortflag); // reset RCB lo/hi bounding box to full simulation box as needed double *lo = rcb->lo; double *hi = rcb->hi; if (lo[0] == shrinklo[0]) lo[0] = boxlo[0]; if (lo[1] == shrinklo[1]) lo[1] = boxlo[1]; if (lo[2] == shrinklo[2]) lo[2] = boxlo[2]; if (hi[0] == shrinkhi[0]) hi[0] = boxhi[0]; if (hi[1] == shrinkhi[1]) hi[1] = boxhi[1]; if (hi[2] == shrinkhi[2]) hi[2] = boxhi[2]; // store RCB cut, dim, lo/hi box in CommTiled // cut and lo/hi need to be in fractional form so can // OK if changes by epsilon from what RCB used since atoms // will subsequently migrate to new owning procs by exchange() anyway // ditto for atoms exactly on lo/hi RCB box boundaries due to ties comm->rcbnew = 1; int idim = rcb->cutdim; if (idim >= 0) comm->rcbcutfrac = (rcb->cut - boxlo[idim]) / prd[idim]; else comm->rcbcutfrac = 0.0; comm->rcbcutdim = idim; double (*mysplit)[2] = comm->mysplit; mysplit[0][0] = (lo[0] - boxlo[0]) / prd[0]; if (hi[0] == boxhi[0]) mysplit[0][1] = 1.0; else mysplit[0][1] = (hi[0] - boxlo[0]) / prd[0]; mysplit[1][0] = (lo[1] - boxlo[1]) / prd[1]; if (hi[1] == boxhi[1]) mysplit[1][1] = 1.0; else mysplit[1][1] = (hi[1] - boxlo[1]) / prd[1]; mysplit[2][0] = (lo[2] - boxlo[2]) / prd[2]; if (hi[2] == boxhi[2]) mysplit[2][1] = 1.0; else mysplit[2][1] = (hi[2] - boxlo[2]) / prd[2]; // return list of procs to send my atoms to return rcb->sendproc; } /* ---------------------------------------------------------------------- setup static load balance operations called from command and indirectly initially from fix balance set rho = 0 for static balancing ------------------------------------------------------------------------- */ void Balance::shift_setup_static(char *str) { shift_allocate = 1; memory->create(proccost,nprocs,"balance:proccost"); memory->create(allproccost,nprocs,"balance:allproccost"); ndim = strlen(str); bdim = new int[ndim]; for (int i = 0; i < ndim; i++) { if (str[i] == 'x') bdim[i] = X; if (str[i] == 'y') bdim[i] = Y; if (str[i] == 'z') bdim[i] = Z; } int max = MAX(comm->procgrid[0],comm->procgrid[1]); max = MAX(max,comm->procgrid[2]); onecost = new double[max]; allcost = new double[max]; sum = new double[max+1]; target = new double[max+1]; lo = new double[max+1]; hi = new double[max+1]; losum = new double[max+1]; hisum = new double[max+1]; // if current layout is TILED, set initial uniform splits in Comm // this gives starting point to subsequent shift balancing if (comm->layout == LAYOUT_TILED) { int *procgrid = comm->procgrid; double *xsplit = comm->xsplit; double *ysplit = comm->ysplit; double *zsplit = comm->zsplit; for (int i = 0; i < procgrid[0]; i++) xsplit[i] = i * 1.0/procgrid[0]; for (int i = 0; i < procgrid[1]; i++) ysplit[i] = i * 1.0/procgrid[1]; for (int i = 0; i < procgrid[2]; i++) zsplit[i] = i * 1.0/procgrid[2]; xsplit[procgrid[0]] = ysplit[procgrid[1]] = zsplit[procgrid[2]] = 1.0; } rho = 0; } /* ---------------------------------------------------------------------- setup shift load balance operations called from fix balance set rho = 1 to do dynamic balancing after call to shift_setup_static() ------------------------------------------------------------------------- */ void Balance::shift_setup(char *str, int nitermax_in, double thresh_in) { shift_setup_static(str); nitermax = nitermax_in; stopthresh = thresh_in; rho = 1; } /* ---------------------------------------------------------------------- load balance by changing xyz split proc boundaries in Comm called one time from input script command or many times from fix balance return niter = iteration count ------------------------------------------------------------------------- */ int Balance::shift() { - int i,j,k,m,np,max; + int i,j,k,m,np; double mycost,totalcost; double *split; // no balancing if no atoms bigint natoms = atom->natoms; if (natoms == 0) return 0; // set delta for 1d balancing = root of threshold // root = # of dimensions being balanced on double delta = pow(stopthresh,1.0/ndim) - 1.0; int *procgrid = comm->procgrid; // all balancing done in lamda coords domain->x2lamda(atom->nlocal); // loop over dimensions in balance string int niter = 0; for (int idim = 0; idim < ndim; idim++) { // split = ptr to xyz split in Comm if (bdim[idim] == X) split = comm->xsplit; else if (bdim[idim] == Y) split = comm->ysplit; else if (bdim[idim] == Z) split = comm->zsplit; else continue; // initial count and sum np = procgrid[bdim[idim]]; tally(bdim[idim],np,split); // target[i] = desired sum at split I if (wtflag) { weight = fixstore->vstore; int nlocal = atom->nlocal; mycost = 0.0; for (i = 0; i < nlocal; i++) mycost += weight[i]; } else mycost = atom->nlocal; MPI_Allreduce(&mycost,&totalcost,1,MPI_DOUBLE,MPI_SUM,world); for (i = 0; i < np; i++) target[i] = totalcost/np * i; target[np] = totalcost; // lo[i] = closest split <= split[i] with a sum <= target // hi[i] = closest split >= split[i] with a sum >= target lo[0] = hi[0] = 0.0; lo[np] = hi[np] = 1.0; losum[0] = hisum[0] = 0.0; losum[np] = hisum[np] = totalcost; for (i = 1; i < np; i++) { for (j = i; j >= 0; j--) if (sum[j] <= target[i]) { lo[i] = split[j]; losum[i] = sum[j]; break; } for (j = i; j <= np; j++) if (sum[j] >= target[i]) { hi[i] = split[j]; hisum[i] = sum[j]; break; } } // iterate until balanced #ifdef BALANCE_DEBUG if (me == 0) debug_shift_output(idim,0,np,split); #endif int doneflag; int change = 1; for (m = 0; m < nitermax; m++) { change = adjust(np,split); tally(bdim[idim],np,split); niter++; #ifdef BALANCE_DEBUG if (me == 0) debug_shift_output(idim,m+1,np,split); if (outflag) dumpout(update->ntimestep); #endif // stop if no change in splits, b/c all targets are met exactly if (!change) break; // stop if all split sums are within delta of targets // this is a 1d test of particle count per slice // assumption is that this is sufficient accuracy // for 3d imbalance factor to reach threshold doneflag = 1; for (i = 1; i < np; i++) if (fabs(1.0*(sum[i]-target[i]))/target[i] > delta) doneflag = 0; if (doneflag) break; } // eliminate final adjacent splits that are duplicates // can happen if particle distribution is narrow and Nitermax is small // set lo = midpt between splits // spread duplicates out evenly between bounding midpts with non-duplicates // i,j = lo/hi indices of set of duplicate splits // delta = new spacing between duplicates // bounding midpts = lo[i-1] and lo[j] int duplicate = 0; for (i = 1; i < np-1; i++) if (split[i] == split[i+1]) duplicate = 1; if (duplicate) { for (i = 0; i < np; i++) lo[i] = 0.5 * (split[i] + split[i+1]); i = 1; while (i < np-1) { j = i+1; while (split[j] == split[i]) j++; j--; if (j > i) { delta = (lo[j] - lo[i-1]) / (j-i+2); for (k = i; k <= j; k++) split[k] = lo[i-1] + (k-i+1)*delta; } i = j+1; } } // sanity check on bad duplicate or inverted splits // zero or negative width sub-domains will break Comm class // should never happen if recursive multisection algorithm is correct int bad = 0; for (i = 0; i < np; i++) if (split[i] >= split[i+1]) bad = 1; if (bad) error->all(FLERR,"Balance produced bad splits"); /* if (me == 0) { printf("BAD SPLITS %d %d %d\n",np+1,niter,delta); for (i = 0; i < np+1; i++) printf(" %g",split[i]); printf("\n"); } */ // stop at this point in bstr if imbalance factor < threshold // this is a true 3d test of particle count per processor double imbfactor = imbalance_splits(); if (imbfactor <= stopthresh) break; } // restore real coords domain->lamda2x(atom->nlocal); return niter; } /* ---------------------------------------------------------------------- count atoms in each slice, based on their dim coordinate N = # of slices split = N+1 cuts between N slices return updated count = particles per slice return updated sum = cumulative count below each of N+1 splits use binary search to find which slice each atom is in ------------------------------------------------------------------------- */ void Balance::tally(int dim, int n, double *split) { for (int i = 0; i < n; i++) onecost[i] = 0.0; double **x = atom->x; int nlocal = atom->nlocal; int index; if (wtflag) { weight = fixstore->vstore; for (int i = 0; i < nlocal; i++) { index = binary(x[i][dim],n,split); onecost[index] += weight[i]; } } else { for (int i = 0; i < nlocal; i++) { index = binary(x[i][dim],n,split); onecost[index] += 1.0; } } MPI_Allreduce(onecost,allcost,n,MPI_DOUBLE,MPI_SUM,world); sum[0] = 0.0; for (int i = 1; i < n+1; i++) sum[i] = sum[i-1] + allcost[i-1]; } /* ---------------------------------------------------------------------- adjust cuts between N slices in a dim via recursive multisectioning method split = current N+1 cuts, with 0.0 and 1.0 at end points sum = cumulative count up to each split target = desired cumulative count up to each split lo/hi = split values that bound current split update lo/hi to reflect sums at current split values overwrite split with new cuts guaranteed that splits will remain in ascending order, though adjacent values may be identical recursive bisectioning zooms in on each cut by halving lo/hi return 0 if no changes in any splits, b/c they are all perfect ------------------------------------------------------------------------- */ int Balance::adjust(int n, double *split) { int i; double fraction; // reset lo/hi based on current sum and splits // insure lo is monotonically increasing, ties are OK // insure hi is monotonically decreasing, ties are OK // this effectively uses info from nearby splits // to possibly tighten bounds on lo/hi for (i = 1; i < n; i++) { if (sum[i] <= target[i]) { lo[i] = split[i]; losum[i] = sum[i]; } if (sum[i] >= target[i]) { hi[i] = split[i]; hisum[i] = sum[i]; } } for (i = 1; i < n; i++) if (lo[i] < lo[i-1]) { lo[i] = lo[i-1]; losum[i] = losum[i-1]; } for (i = n-1; i > 0; i--) if (hi[i] > hi[i+1]) { hi[i] = hi[i+1]; hisum[i] = hisum[i+1]; } int change = 0; for (int i = 1; i < n; i++) if (sum[i] != target[i]) { change = 1; if (rho == 0) split[i] = 0.5 * (lo[i]+hi[i]); else { fraction = 1.0*(target[i]-losum[i]) / (hisum[i]-losum[i]); split[i] = lo[i] + fraction * (hi[i]-lo[i]); } } return change; } /* ---------------------------------------------------------------------- calculate imbalance based on processor splits in 3 dims atoms must be in lamda coords (0-1) before called map particles to 3d grid of procs return imbalance factor = max load per proc / ave load per proc ------------------------------------------------------------------------- */ double Balance::imbalance_splits() { double *xsplit = comm->xsplit; double *ysplit = comm->ysplit; double *zsplit = comm->zsplit; int nx = comm->procgrid[0]; int ny = comm->procgrid[1]; int nz = comm->procgrid[2]; for (int i = 0; i < nprocs; i++) proccost[i] = 0.0; double **x = atom->x; int nlocal = atom->nlocal; int ix,iy,iz; if (wtflag) { weight = fixstore->vstore; for (int i = 0; i < nlocal; i++) { ix = binary(x[i][0],nx,xsplit); iy = binary(x[i][1],ny,ysplit); iz = binary(x[i][2],nz,zsplit); proccost[iz*nx*ny + iy*nx + ix] += weight[i]; } } else { for (int i = 0; i < nlocal; i++) { ix = binary(x[i][0],nx,xsplit); iy = binary(x[i][1],ny,ysplit); iz = binary(x[i][2],nz,zsplit); proccost[iz*nx*ny + iy*nx + ix] += 1.0; } } // one proc's particles may map to many partitions, so must Allreduce MPI_Allreduce(proccost,allproccost,nprocs,MPI_DOUBLE,MPI_SUM,world); double maxcost = 0.0; double totalcost = 0.0; for (int i = 0; i < nprocs; i++) { maxcost = MAX(maxcost,allproccost[i]); totalcost += allproccost[i]; } double imbalance = 1.0; if (maxcost > 0.0) imbalance = maxcost / (totalcost/nprocs); return imbalance; } /* ---------------------------------------------------------------------- binary search for where value falls in N-length vec note that vec actually has N+1 values, but ignore last one values in vec are monotonically increasing, but adjacent values can be ties value may be outside range of vec limits always return index from 0 to N-1 inclusive return 0 if value < vec[0] reutrn N-1 if value >= vec[N-1] return index = 1 to N-2 inclusive if vec[index] <= value < vec[index+1] note that for adjacent tie values, index of lower tie is not returned since never satisfies 2nd condition that value < vec[index+1] ------------------------------------------------------------------------- */ int Balance::binary(double value, int n, double *vec) { int lo = 0; int hi = n-1; if (value < vec[lo]) return lo; if (value >= vec[hi]) return hi; // insure vec[lo] <= value < vec[hi] at every iteration // done when lo,hi are adjacent int index = (lo+hi)/2; while (lo < hi-1) { if (value < vec[index]) hi = index; else if (value >= vec[index]) lo = index; index = (lo+hi)/2; } return index; } /* ---------------------------------------------------------------------- write dump snapshot of line segments in Pizza.py mdump mesh format write xy lines around each proc's sub-domain for 2d write xyz cubes around each proc's sub-domain for 3d only called by proc 0 NOTE: only implemented for orthogonal boxes, not triclinic ------------------------------------------------------------------------- */ void Balance::dumpout(bigint tstep) { int dimension = domain->dimension; int triclinic = domain->triclinic; // Allgather each proc's sub-box // could use Gather, but that requires MPI to alloc memory double *lo,*hi; if (triclinic == 0) { lo = domain->sublo; hi = domain->subhi; } else { lo = domain->sublo_lamda; hi = domain->subhi_lamda; } double box[6]; box[0] = lo[0]; box[1] = lo[1]; box[2] = lo[2]; box[3] = hi[0]; box[4] = hi[1]; box[5] = hi[2]; double **boxall; memory->create(boxall,nprocs,6,"balance:dumpout"); MPI_Allgather(box,6,MPI_DOUBLE,&boxall[0][0],6,MPI_DOUBLE,world); if (me) { memory->destroy(boxall); return; } // proc 0 writes out nodal coords // some will be duplicates double *boxlo = domain->boxlo; double *boxhi = domain->boxhi; fprintf(fp,"ITEM: TIMESTEP\n"); fprintf(fp,BIGINT_FORMAT "\n",tstep); fprintf(fp,"ITEM: NUMBER OF NODES\n"); if (dimension == 2) fprintf(fp,"%d\n",4*nprocs); else fprintf(fp,"%d\n",8*nprocs); fprintf(fp,"ITEM: BOX BOUNDS\n"); fprintf(fp,"%g %g\n",boxlo[0],boxhi[0]); fprintf(fp,"%g %g\n",boxlo[1],boxhi[1]); fprintf(fp,"%g %g\n",boxlo[2],boxhi[2]); fprintf(fp,"ITEM: NODES\n"); if (triclinic == 0) { if (dimension == 2) { int m = 0; for (int i = 0; i < nprocs; i++) { fprintf(fp,"%d %d %g %g %g\n",m+1,1,boxall[i][0],boxall[i][1],0.0); fprintf(fp,"%d %d %g %g %g\n",m+2,1,boxall[i][3],boxall[i][1],0.0); fprintf(fp,"%d %d %g %g %g\n",m+3,1,boxall[i][3],boxall[i][4],0.0); fprintf(fp,"%d %d %g %g %g\n",m+4,1,boxall[i][0],boxall[i][4],0.0); m += 4; } } else { int m = 0; for (int i = 0; i < nprocs; i++) { fprintf(fp,"%d %d %g %g %g\n",m+1,1, boxall[i][0],boxall[i][1],boxall[i][2]); fprintf(fp,"%d %d %g %g %g\n",m+2,1, boxall[i][3],boxall[i][1],boxall[i][2]); fprintf(fp,"%d %d %g %g %g\n",m+3,1, boxall[i][3],boxall[i][4],boxall[i][2]); fprintf(fp,"%d %d %g %g %g\n",m+4,1, boxall[i][0],boxall[i][4],boxall[i][2]); fprintf(fp,"%d %d %g %g %g\n",m+5,1, boxall[i][0],boxall[i][1],boxall[i][5]); fprintf(fp,"%d %d %g %g %g\n",m+6,1, boxall[i][3],boxall[i][1],boxall[i][5]); fprintf(fp,"%d %d %g %g %g\n",m+7,1, boxall[i][3],boxall[i][4],boxall[i][5]); fprintf(fp,"%d %d %g %g %g\n",m+8,1, boxall[i][0],boxall[i][4],boxall[i][5]); m += 8; } } } else { double (*bc)[3] = domain->corners; if (dimension == 2) { int m = 0; for (int i = 0; i < nprocs; i++) { domain->lamda_box_corners(&boxall[i][0],&boxall[i][3]); fprintf(fp,"%d %d %g %g %g\n",m+1,1,bc[0][0],bc[0][1],0.0); fprintf(fp,"%d %d %g %g %g\n",m+2,1,bc[1][0],bc[1][1],0.0); fprintf(fp,"%d %d %g %g %g\n",m+3,1,bc[2][0],bc[2][1],0.0); fprintf(fp,"%d %d %g %g %g\n",m+4,1,bc[3][0],bc[3][1],0.0); m += 4; } } else { int m = 0; for (int i = 0; i < nprocs; i++) { domain->lamda_box_corners(&boxall[i][0],&boxall[i][3]); fprintf(fp,"%d %d %g %g %g\n",m+1,1,bc[0][0],bc[0][1],bc[0][1]); fprintf(fp,"%d %d %g %g %g\n",m+2,1,bc[1][0],bc[1][1],bc[1][1]); fprintf(fp,"%d %d %g %g %g\n",m+3,1,bc[2][0],bc[2][1],bc[2][1]); fprintf(fp,"%d %d %g %g %g\n",m+4,1,bc[3][0],bc[3][1],bc[3][1]); fprintf(fp,"%d %d %g %g %g\n",m+5,1,bc[4][0],bc[4][1],bc[4][1]); fprintf(fp,"%d %d %g %g %g\n",m+6,1,bc[5][0],bc[5][1],bc[5][1]); fprintf(fp,"%d %d %g %g %g\n",m+7,1,bc[6][0],bc[6][1],bc[6][1]); fprintf(fp,"%d %d %g %g %g\n",m+8,1,bc[7][0],bc[7][1],bc[7][1]); m += 8; } } } // write out one square/cube per processor for 2d/3d fprintf(fp,"ITEM: TIMESTEP\n"); fprintf(fp,BIGINT_FORMAT "\n",tstep); if (dimension == 2) fprintf(fp,"ITEM: NUMBER OF SQUARES\n"); else fprintf(fp,"ITEM: NUMBER OF CUBES\n"); fprintf(fp,"%d\n",nprocs); if (dimension == 2) fprintf(fp,"ITEM: SQUARES\n"); else fprintf(fp,"ITEM: CUBES\n"); if (dimension == 2) { int m = 0; for (int i = 0; i < nprocs; i++) { fprintf(fp,"%d %d %d %d %d %d\n",i+1,1,m+1,m+2,m+3,m+4); m += 4; } } else { int m = 0; for (int i = 0; i < nprocs; i++) { fprintf(fp,"%d %d %d %d %d %d %d %d %d %d\n", i+1,1,m+1,m+2,m+3,m+4,m+5,m+6,m+7,m+8); m += 8; } } memory->destroy(boxall); } /* ---------------------------------------------------------------------- debug output for Idim and count only called by proc 0 ------------------------------------------------------------------------- */ #ifdef BALANCE_DEBUG void Balance::debug_shift_output(int idim, int m, int np, double *split) { int i; const char *dim = NULL; double *boxlo = domain->boxlo; double *prd = domain->prd; if (bdim[idim] == X) dim = "X"; else if (bdim[idim] == Y) dim = "Y"; else if (bdim[idim] == Z) dim = "Z"; fprintf(stderr,"Dimension %s, Iteration %d\n",dim,m); fprintf(stderr," Count:"); for (i = 0; i < np; i++) fprintf(stderr," " BIGINT_FORMAT,count[i]); fprintf(stderr,"\n"); fprintf(stderr," Sum:"); for (i = 0; i <= np; i++) fprintf(stderr," " BIGINT_FORMAT,sum[i]); fprintf(stderr,"\n"); fprintf(stderr," Target:"); for (i = 0; i <= np; i++) fprintf(stderr," " BIGINT_FORMAT,target[i]); fprintf(stderr,"\n"); fprintf(stderr," Actual cut:"); for (i = 0; i <= np; i++) fprintf(stderr," %g",boxlo[bdim[idim]] + split[i]*prd[bdim[idim]]); fprintf(stderr,"\n"); fprintf(stderr," Split:"); for (i = 0; i <= np; i++) fprintf(stderr," %g",split[i]); fprintf(stderr,"\n"); fprintf(stderr," Low:"); for (i = 0; i <= np; i++) fprintf(stderr," %g",lo[i]); fprintf(stderr,"\n"); fprintf(stderr," Low-sum:"); for (i = 0; i <= np; i++) fprintf(stderr," " BIGINT_FORMAT,losum[i]); fprintf(stderr,"\n"); fprintf(stderr," Hi:"); for (i = 0; i <= np; i++) fprintf(stderr," %g",hi[i]); fprintf(stderr,"\n"); fprintf(stderr," Hi-sum:"); for (i = 0; i <= np; i++) fprintf(stderr," " BIGINT_FORMAT,hisum[i]); fprintf(stderr,"\n"); fprintf(stderr," Delta:"); for (i = 0; i < np; i++) fprintf(stderr," %g",split[i+1]-split[i]); fprintf(stderr,"\n"); bigint max = 0; for (i = 0; i < np; i++) max = MAX(max,count[i]); fprintf(stderr," Imbalance factor: %g\n",1.0*max*np/target[np]); } #endif