void computeOrdering(const ordinal_type treecut = 0) {
int ierr = 0;
// pointers for global graph ordering
ordinal_type *perm = _perm.ptr_on_device();
ordinal_type *peri = _peri.ptr_on_device();
ordinal_type *range = _range.ptr_on_device();
ordinal_type *tree = _tree.ptr_on_device();
{
// set desired tree level
if (_strat & SCOTCH_STRATLEVELMAX ||
_strat & SCOTCH_STRATLEVELMIN) {
TACHO_TEST_FOR_ABORT(_level == 0, "SCOTCH_STRATLEVEL(MIN/MAX) is used but level is not specified");
}
const int level = Util::max(1, _level-treecut);
SCOTCH_Strat stradat;
SCOTCH_Num straval = _strat;
ierr = SCOTCH_stratInit(&stradat);
TACHO_TEST_FOR_ABORT(ierr, "Failed in SCOTCH_stratInit");
// if both are zero, do not build strategy
if (_strat || _level) {
if (_verbose)
std::cout << "GraphTools_Scotch:: User provide a strategy and/or level" << std::endl
<< " strategy = " << _strat << ", level = " << _level << ", treecut = " << treecut << std::endl
<< " strategy & SCOTCH_STRATLEVELMAX = " << (_strat & SCOTCH_STRATLEVELMAX) << std::endl
<< " strategy & SCOTCH_STRATLEVELMIN = " << (_strat & SCOTCH_STRATLEVELMIN) << std::endl
<< " strategy & SCOTCH_STRATLEAFSIMPLE = " << (_strat & SCOTCH_STRATLEAFSIMPLE) << std::endl
<< " strategy & SCOTCH_STRATSEPASIMPLE = " << (_strat & SCOTCH_STRATSEPASIMPLE) << std::endl
<< std::endl;
ierr = SCOTCH_stratGraphOrderBuild(&stradat, straval, level, 0.2);
TACHO_TEST_FOR_ABORT(ierr, "Failed in SCOTCH_stratGraphOrderBuild");
}
ierr = SCOTCH_graphOrder(&_graph,
&stradat,
perm,
peri,
&_cblk,
range,
tree);
TACHO_TEST_FOR_ABORT(ierr, "Failed in SCOTCH_graphOrder");
SCOTCH_stratExit(&stradat);
}
{
ordinal_type nroot = 0;
for (ordinal_type i=0; i<_cblk; ++i)
nroot += (_tree[i] == -1);
if (nroot > 1) {
if (_verbose)
std::cout << "GraphTools_Scotch:: # of roots " << nroot << std::endl
<< " a fake root is created to complete the tree" << std::endl
<< std::endl;
_tree [_cblk] = -1; // dummy root
_range[_cblk+1] = _range[_cblk]; // zero range for the dummy root
for (ordinal_type i=0; i<_cblk; ++i)
if (_tree[i] == -1) // multiple roots becomes children of the dummy root
_tree[i] = (_cblk+1);
++_cblk; // include the dummy root
}
}
_is_ordered = true;
//std::cout << "SCOTCH level = " << level << std::endl;
//std::cout << "Range Tree " << std::endl;
//for (int i=0;i<_cblk;++i)
// std::cout << _range[i] << " :: " << i << " " << _tree[i] << std::endl;
}
bool
ScotchSplitter(unsigned dim,
const int* ptRows, const int* indCols,
unsigned& nbMaxLevels, unsigned minSize,
int* loc2glob, int* glob2loc, int& nbDoms,
int*& ptOnDomains, int*& sizeOfDomains,
bool checkData, const bool verbose, FILE *fp)
{
int ierr;
// check consistency between Scotch and Dissection library
CHECK(sizeof(int) == sizeof(SCOTCH_Num),
"Incompatible integer representation between Scotch and Dissection");
if (verbose) {
int vers, rela, patc;
SCOTCH_version(&vers, &rela, &patc);
diss_printf(verbose, fp, "%s %d : Soctch version : %d.%d.%d\n",
__FILE__, __LINE__, vers, rela, patc);
}
// Allocate and initialize the Scotch graph
SCOTCH_Graph ptGraph;
ierr = SCOTCH_graphInit(&ptGraph);
CHECK(ierr==0,"Fail initializing Scotch graph");
// TRACE("Building Scotch graph\n");
ierr = SCOTCH_graphBuild(&ptGraph,
(SCOTCH_Num)0, // offset,
(SCOTCH_Num)dim,
(const SCOTCH_Num*)ptRows,
(const SCOTCH_Num*)ptRows+1,
NULL, NULL, (SCOTCH_Num)ptRows[dim],
(const SCOTCH_Num*)indCols, NULL);
// if (verbose) {
// fprintf(fp, "%s %d : 1 : ptRows = %p indCols = %p\n",
// __FILE__, __LINE__, (void *)ptRows, (void *)indCols);
// }
CHECK(ierr==0,"Scotch graph building failed !");
if (checkData) {
//TRACE("Check Scotch graph\n");
ierr = SCOTCH_graphCheck(&ptGraph);
if (ierr) {
diss_printf(verbose, fp,
"Failed the checking of the graph : bad data ?\n");
SCOTCH_graphFree(&ptGraph);
return false;
}
}
// Allocate and initialize the strategy wanted for Scotch
// TRACE("Initialize strategy for splitting\n");
SCOTCH_Strat ptStrat;
ierr = SCOTCH_stratInit(&ptStrat);
CHECK(ierr==0,
"Failed initializing Scotch strategy structure");
char *str_Strat = new char[1024];
int nbLvls = std::min(unsigned(nbMaxLevels),
highestbit(unsigned(dim/minSize)));
diss_printf(verbose, fp, "nbLevels = %d\n", nbLvls);
sprintf(str_Strat,"c{rat=0.7,cpr=n{sep=/((levl<%d)|(vert>%d))?m{type=h,rat=0.7,vert=100,low=h{pass=10},asc=b{width=3,bnd=f{bal=0.2},org=h{pass=10}f{bal=0.2}}}|m{type=h,rat=0.7,vert=100,low=h{pass=10},asc=b{width=3,bnd=f{bal=0.2},org=h{pass=10}f{bal=0.2}}};,ole=f{cmin=%d,cmax=%d,frat=0.05},ose=s},unc=n{sep=/(levl<%d)?(m{type=h,rat=0.7,vert=100,low=h{pass=10},asc=b{width=3,bnd=f{bal=0.2},org=h{pass=10}f{bal=0.2}}})|m{type=h,rat=0.7,vert=100,low=h{pass=10},asc=b{width=3,bnd=f{bal=0.2},org=h{pass=10}f{bal=0.2}}};,ole=f{cmin=%d,cmax=%d,frat=0.05},ose=s}}",
nbLvls-1,2*minSize-1,minSize,dim,nbLvls-1,minSize,dim);
// DBG_PRINT("Strategy string : %s\n", str_Strat);
ierr = SCOTCH_stratGraphOrder(&ptStrat, str_Strat);
delete [] str_Strat;
CHECK(ierr==0,
"Failed build graph ordering strategy for Scotch");
// Ordering with nested bisection :
// TRACE("Split the graph\n");
int* rangtab = new int[dim+1];
int* treetab = new int[dim];
int nbSplitDoms;
bool repeat = true;
int lastCompleteLevel;
int *levels, *nbDomsPerLevels;
SCOTCH_randomReset();
while (repeat) {
ierr = SCOTCH_graphOrder(&ptGraph, &ptStrat,
(SCOTCH_Num*)loc2glob,
(SCOTCH_Num*)glob2loc,
(SCOTCH_Num*)&nbSplitDoms,
(SCOTCH_Num*)rangtab,
(SCOTCH_Num*)treetab);
if (ierr) {
diss_printf(verbose, fp, "Failed reordering sparse matrix graph !\n");
SCOTCH_stratExit(&ptStrat);
SCOTCH_graphFree(&ptGraph);
return false;
}
levels = new int[nbSplitDoms];
// int *nbDomsPerLevels;// = new int[nbLvls];
unsigned nbLvlsScotch= compLevelOfDoms(nbSplitDoms, nbLvls, treetab, levels,
nbDomsPerLevels);
/** Search last level where number of domains is a power of two
*/
lastCompleteLevel = 0;
while ((lastCompleteLevel<nbLvlsScotch) &&
((1<<lastCompleteLevel) == nbDomsPerLevels[lastCompleteLevel]) ) {
lastCompleteLevel ++;
}
lastCompleteLevel = std::min(lastCompleteLevel, nbLvls);
nbDoms = (1<<lastCompleteLevel)-1;
// Search where start each domain per bisection level
// and compute the size of each subdomain :
// int indDom = 0;
bool flag_size_check = false;
for (int i = 0; i < nbSplitDoms; i++) {
int sz = 0;
while (levels[i]>=lastCompleteLevel) {
sz += rangtab[i+1]-rangtab[i];
i++;
}
if (sz+rangtab[i+1]-rangtab[i] <= TOO_SMALL) {
flag_size_check = true;
break;
}
//DBG_PRINT("Domain %d begin at %d\n",indDom+1,begDom);
} // loop : i
if (!flag_size_check) {
repeat = false;
break;
}
else {
delete [] levels;
delete [] nbDomsPerLevels;
}
} // while (repeat)
ptOnDomains = new int[nbDoms+1];
sizeOfDomains = new int[nbDoms];
memset(sizeOfDomains, 0, nbDoms*sizeof(int));
int* indDomPerLevel = new int[lastCompleteLevel+1];
memset(indDomPerLevel,0,(lastCompleteLevel+1)*sizeof(int));
int begDom = 0;
for (int i = 0; i < nbSplitDoms; i++) {
int sz = 0;
while (levels[i]>=lastCompleteLevel) {
sz += rangtab[i+1]-rangtab[i];
i++;
}
int indDom = (1<<levels[i])-1+indDomPerLevel[levels[i]];
// DBG_PRINT("level %d : current dom = %d\n", levels[i],indDom+1);
ptOnDomains[indDom] = begDom;
//DBG_PRINT("Domain %d begin at %d\n",indDom+1,begDom);
sizeOfDomains[indDom] = sz+rangtab[i+1]-rangtab[i];
//DBG_PRINT("Domain %d size of %d\n",indDom+1,sizeOfDomains[indDom]);
begDom += sizeOfDomains[indDom];
indDomPerLevel[levels[i]] += 1;
}
diss_printf(verbose, fp, "%s %d : indDomPerlevel[lastCompleteLevel] = %d\n",
__FILE__, __LINE__, indDomPerLevel[lastCompleteLevel]);
ptOnDomains[nbDoms] = dim;
nbMaxLevels = lastCompleteLevel;
delete [] indDomPerLevel;
delete [] nbDomsPerLevels;
delete [] levels;
delete [] treetab;
delete [] rangtab;
// Cleaning all Scotch structures :
SCOTCH_stratExit(&ptStrat);
SCOTCH_graphFree(&ptGraph);
return true;
}
