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Reference Guide
MPIProcess.cxx
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1 // @(#)root/minuit2:$Id$
2 // Author: A. Lazzaro 2009
3 /***************************************************************************
4  * Package: Minuit2 *
5  * File: $Id$ *
6  * Author: Alfio Lazzaro, alfio.lazzaro@mi.infn.it *
7  * *
8  * Copyright: (C) 2008 by Universita' and INFN, Milan *
9  ***************************************************************************/
10 
11 #include "Minuit2/MPIProcess.h"
12 
13 #include <iostream>
14 
15 namespace ROOT {
16 
17 namespace Minuit2 {
18 
19  unsigned int MPIProcess::fgGlobalSize = 1;
20  unsigned int MPIProcess::fgGlobalRank = 0;
21 
22  // By default all procs are for X
23  unsigned int MPIProcess::fgCartSizeX = 0;
24  unsigned int MPIProcess::fgCartSizeY = 0;
25  unsigned int MPIProcess::fgCartDimension = 0;
26  bool MPIProcess::fgNewCart = true;
27 
28 #ifdef MPIPROC
29  MPI::Intracomm* MPIProcess::fgCommunicator = 0;
30  int MPIProcess::fgIndexComm = -1; // -1 for no-initialization
31  MPI::Intracomm* MPIProcess::fgCommunicators[2] = {0};
32  unsigned int MPIProcess::fgIndecesComm[2] = {0};
33 #endif
34 
35  MPIProcess::MPIProcess(unsigned int nelements, unsigned int indexComm) :
36  fNelements(nelements), fSize(1), fRank(0)
37  {
38 
39  // check local requested index for communicator, valid values are 0 and 1
40  indexComm = (indexComm==0) ? 0 : 1;
41 
42 #ifdef MPIPROC
43 
44  StartMPI();
45 
48  //declare the cartesian topology
49 
50  if (fgCommunicator==0 && fgIndexComm<0 && fgNewCart) {
51  // first call, declare the topology
52  std::cout << "Info --> MPIProcess::MPIProcess: Declare cartesian Topology ("
53  << fgCartSizeX << "x" << fgCartSizeY << ")" << std::endl;
54 
55  int color = fgGlobalRank / fgCartSizeY;
56  int key = fgGlobalRank % fgCartSizeY;
57 
58  fgCommunicators[0] = new MPI::Intracomm(MPI::COMM_WORLD.Split(key,color)); // rows for Minuit
59  fgCommunicators[1] = new MPI::Intracomm(MPI::COMM_WORLD.Split(color,key)); // columns for NLL
60 
61  fgNewCart = false;
62 
63  }
64 
65  fgIndexComm++;
66 
67  if (fgIndexComm>1 || fgCommunicator==(&(MPI::COMM_WORLD))) { // Remember, no more than 2 dimensions in the topology!
68  std::cerr << "Error --> MPIProcess::MPIProcess: Requiring more than 2 dimensions in the topology!" << std::endl;
69  MPI::COMM_WORLD.Abort(-1);
70  }
71 
72  // requiring columns as first call. In this case use all nodes
73  if (((unsigned int)fgIndexComm)<indexComm)
74  fgCommunicator = &(MPI::COMM_WORLD);
75  else {
76  fgIndecesComm[fgIndexComm] = indexComm;
77  fgCommunicator = fgCommunicators[fgIndecesComm[fgIndexComm]];
78  }
79 
80  }
81  else {
82  // no cartesian topology
84  std::cout << "Warning --> MPIProcess::MPIProcess: Cartesian dimension doesn't correspond to # total procs!" << std::endl;
85  std::cout << "Warning --> MPIProcess::MPIProcess: Ignoring topology, use all procs for X." << std::endl;
86  std::cout << "Warning --> MPIProcess::MPIProcess: Resetting topology..." << std::endl;
88  fgCartSizeY = 1;
90  }
91 
92  if (fgIndexComm<0) {
94  fgCommunicators[0] = &(MPI::COMM_WORLD);
95  fgCommunicators[1] = 0;
96  }
97  else {
98  fgCommunicators[0] = 0;
99  fgCommunicators[1] = &(MPI::COMM_WORLD);
100  }
101  }
102 
103  fgIndexComm++;
104 
105  if (fgIndexComm>1) { // Remember, no more than 2 nested MPI calls!
106  std::cerr << "Error --> MPIProcess::MPIProcess: More than 2 nested MPI calls!" << std::endl;
107  MPI::COMM_WORLD.Abort(-1);
108  }
109 
110  fgIndecesComm[fgIndexComm] = indexComm;
111 
112  // require 2 nested communicators
113  if (fgCommunicator!=0 && fgCommunicators[indexComm]!=0) {
114  std::cout << "Warning --> MPIProcess::MPIProcess: Requiring 2 nested MPI calls!" << std::endl;
115  std::cout << "Warning --> MPIProcess::MPIProcess: Ignoring second call." << std::endl;
116  fgIndecesComm[fgIndexComm] = (indexComm==0) ? 1 : 0;
117  }
118 
119  fgCommunicator = fgCommunicators[fgIndecesComm[fgIndexComm]];
120 
121  }
122 
123  // set size and rank
124  if (fgCommunicator!=0) {
125  fSize = fgCommunicator->Get_size();
126  fRank = fgCommunicator->Get_rank();
127  }
128  else {
129  // no MPI calls
130  fSize = 1;
131  fRank = 0;
132  }
133 
134 
135  if (fSize>fNelements) {
136  std::cerr << "Error --> MPIProcess::MPIProcess: more processors than elements!" << std::endl;
137  MPI::COMM_WORLD.Abort(-1);
138  }
139 
140 #endif
141 
144 
145  }
146 
148  {
149  // destructor
150 #ifdef MPIPROC
151  fgCommunicator = 0;
152  fgIndexComm--;
153  if (fgIndexComm==0)
154  fgCommunicator = fgCommunicators[fgIndecesComm[fgIndexComm]];
155 
156 #endif
157 
158  }
159 
161  {
162 
163  // In case of just one job, don't need sync, just go
164  if (fSize<2)
165  return false;
166 
167  if (mnvector.size()!=fNelements) {
168  std::cerr << "Error --> MPIProcess::SyncVector: # defined elements different from # requested elements!" << std::endl;
169  std::cerr << "Error --> MPIProcess::SyncVector: no MPI syncronization is possible!" << std::endl;
170  exit(-1);
171  }
172 
173 #ifdef MPIPROC
174  unsigned int numElements4ThisJob = NumElements4Job(fRank);
175  unsigned int startElementIndex = StartElementIndex();
176  unsigned int endElementIndex = EndElementIndex();
177 
178  double dvectorJob[numElements4ThisJob];
179  for(unsigned int i = startElementIndex; i<endElementIndex; i++)
180  dvectorJob[i-startElementIndex] = mnvector(i);
181 
182  double dvector[fNelements];
183  MPISyncVector(dvectorJob,numElements4ThisJob,dvector);
184 
185  for (unsigned int i = 0; i<fNelements; i++) {
186  mnvector(i) = dvector[i];
187  }
188 
189  return true;
190 
191 #else
192 
193  std::cerr << "Error --> MPIProcess::SyncVector: no MPI syncronization is possible!" << std::endl;
194  exit(-1);
195 
196 #endif
197 
198  }
199 
200 
202  {
203 
204  // In case of just one job, don't need sync, just go
205  if (fSize<2)
206  return false;
207 
208  if (mnmatrix.size()-mnmatrix.Nrow()!=fNelements) {
209  std::cerr << "Error --> MPIProcess::SyncSymMatrixOffDiagonal: # defined elements different from # requested elements!" << std::endl;
210  std::cerr << "Error --> MPIProcess::SyncSymMatrixOffDiagonal: no MPI syncronization is possible!" << std::endl;
211  exit(-1);
212  }
213 
214 #ifdef MPIPROC
215  unsigned int numElements4ThisJob = NumElements4Job(fRank);
216  unsigned int startElementIndex = StartElementIndex();
217  unsigned int endElementIndex = EndElementIndex();
218  unsigned int nrow = mnmatrix.Nrow();
219 
220  unsigned int offsetVect = 0;
221  for (unsigned int i = 0; i<startElementIndex; i++)
222  if ((i+offsetVect)%(nrow-1)==0) offsetVect += (i+offsetVect)/(nrow-1);
223 
224  double dvectorJob[numElements4ThisJob];
225  for(unsigned int i = startElementIndex; i<endElementIndex; i++) {
226 
227  int x = (i+offsetVect)/(nrow-1);
228  if ((i+offsetVect)%(nrow-1)==0) offsetVect += x;
229  int y = (i+offsetVect)%(nrow-1)+1;
230 
231  dvectorJob[i-startElementIndex] = mnmatrix(x,y);
232 
233  }
234 
235  double dvector[fNelements];
236  MPISyncVector(dvectorJob,numElements4ThisJob,dvector);
237 
238  offsetVect = 0;
239  for (unsigned int i = 0; i<fNelements; i++) {
240 
241  int x = (i+offsetVect)/(nrow-1);
242  if ((i+offsetVect)%(nrow-1)==0) offsetVect += x;
243  int y = (i+offsetVect)%(nrow-1)+1;
244 
245  mnmatrix(x,y) = dvector[i];
246 
247  }
248 
249  return true;
250 
251 #else
252 
253  std::cerr << "Error --> MPIProcess::SyncMatrix: no MPI syncronization is possible!" << std::endl;
254  exit(-1);
255 
256 #endif
257 
258  }
259 
260 #ifdef MPIPROC
261  void MPIProcess::MPISyncVector(double *ivector, int svector, double *ovector)
262  {
263  int offsets[fSize];
264  int nconts[fSize];
265  nconts[0] = NumElements4Job(0);
266  offsets[0] = 0;
267  for (unsigned int i = 1; i<fSize; i++) {
268  nconts[i] = NumElements4Job(i);
269  offsets[i] = nconts[i-1] + offsets[i-1];
270  }
271 
272  fgCommunicator->Allgatherv(ivector,svector,MPI::DOUBLE,
273  ovector,nconts,offsets,MPI::DOUBLE);
274 
275  }
276 
277  bool MPIProcess::SetCartDimension(unsigned int dimX, unsigned int dimY)
278  {
279  if (fgCommunicator!=0 || fgIndexComm>=0) {
280  std::cout << "Warning --> MPIProcess::SetCartDimension: MPIProcess already declared! Ignoring command..." << std::endl;
281  return false;
282  }
283  if (dimX*dimY<=0) {
284  std::cout << "Warning --> MPIProcess::SetCartDimension: Invalid topology! Ignoring command..." << std::endl;
285  return false;
286  }
287 
288  StartMPI();
289 
290  if (fgGlobalSize!=dimX*dimY) {
291  std::cout << "Warning --> MPIProcess::SetCartDimension: Cartesian dimension doesn't correspond to # total procs!" << std::endl;
292  std::cout << "Warning --> MPIProcess::SetCartDimension: Ignoring command..." << std::endl;
293  return false;
294  }
295 
296  if (fgCartSizeX!=dimX || fgCartSizeY!=dimY) {
297  fgCartSizeX = dimX; fgCartSizeY = dimY;
299  fgNewCart = true;
300 
301  if (fgCommunicators[0]!=0 && fgCommunicators[1]!=0) {
302  delete fgCommunicators[0]; fgCommunicators[0] = 0; fgIndecesComm[0] = 0;
303  delete fgCommunicators[1]; fgCommunicators[1] = 0; fgIndecesComm[1] = 0;
304  }
305  }
306 
307  return true;
308 
309  }
310 
311  bool MPIProcess::SetDoFirstMPICall(bool doFirstMPICall)
312  {
313 
314  StartMPI();
315 
316  bool ret;
317  if (doFirstMPICall)
319  else
321 
322  return ret;
323 
324  }
325 
326 #endif
327 
328 #ifdef MPIPROC
329  MPITerminate dummyMPITerminate = MPITerminate();
330 #endif
331 
332 } // namespace Minuit2
333 
334 } // namespace ROOT
unsigned int fNumElements4JobOut
Definition: MPIProcess.h:129
#define Split(a, ahi, alo)
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This namespace contains pre-defined functions to be used in conjuction with TExecutor::Map and TExecu...
Definition: StringConv.hxx:21
static unsigned int fgGlobalSize
Definition: MPIProcess.h:120
MPIProcess(unsigned int nelements, unsigned int indexComm)
Definition: MPIProcess.cxx:35
bool SyncVector(ROOT::Minuit2::MnAlgebraicVector &mnvector)
Definition: MPIProcess.cxx:160
static void StartMPI()
Definition: MPIProcess.h:71
Class describing a symmetric matrix of size n.
Definition: LASymMatrix.h:51
static unsigned int fgCartDimension
Definition: MPIProcess.h:125
unsigned int fNumElements4JobIn
Definition: MPIProcess.h:128
unsigned int EndElementIndex() const
Definition: MPIProcess.h:60
static bool SetDoFirstMPICall(bool doFirstMPICall=true)
static bool SetCartDimension(unsigned int dimX, unsigned int dimY)
Double_t x[n]
Definition: legend1.C:17
unsigned int StartElementIndex() const
Definition: MPIProcess.h:56
static unsigned int fgCartSizeX
Definition: MPIProcess.h:123
static unsigned int fgGlobalRank
Definition: MPIProcess.h:121
unsigned int NumElements4Job(unsigned int rank) const
Definition: MPIProcess.h:53
unsigned int Nrow() const
Definition: LASymMatrix.h:239
unsigned int size() const
Definition: LAVector.h:198
static unsigned int fgCartSizeY
Definition: MPIProcess.h:124
Double_t y[n]
Definition: legend1.C:17
unsigned int size() const
Definition: LASymMatrix.h:237
bool SyncSymMatrixOffDiagonal(ROOT::Minuit2::MnAlgebraicSymMatrix &mnmatrix)
Definition: MPIProcess.cxx:201