Merge pull request trilinos#6326 from lucbv/MueLu_aggregation_kokkos_…

…fixes MueLu: fixing the count of aggregated nodes in refactored Phase2a of aggregation, see trilinos#6325
tcad-charon · Nov 22, 2019 · e55a0e5 · e55a0e5
2 parents 800c07e + e1190ac
commit e55a0e5
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Showing 2 changed files with 30 additions and 9 deletions.
diff --git a/...ges/muelu/src/Graph/UncoupledAggregation/MueLu_AggregationPhase2aAlgorithm_kokkos_def.hpp b/...ges/muelu/src/Graph/UncoupledAggregation/MueLu_AggregationPhase2aAlgorithm_kokkos_def.hpp
@@ -136,14 +136,20 @@ namespace MueLu {
 
                                   // Loop over neighbors to count how many nodes could join
                                   // the new aggregate
+                                  // Note on 2019-11-22, LBV:
+                                  // The rootCandidate is not taken into account and in fact
+                                  // not aggregatesd later on. To change that we want to
+                                  // modify:
+                                  // if(aggSize < maxNodesPerAggregate)
+                                  // to:
+                                  // if(aggSize < maxNodesPerAggregate - 1)
                                   LO numNeighbors = 0;
                                   for(int j = 0; j < neighbors.length; ++j) {
                                     LO neigh = neighbors(j);
                                     if(neigh != rootCandidate) {
                                       if(graph.isLocalNeighborVertex(neigh) &&
-                                         aggStat(neigh) == READY &&
-                                         aggSize < maxNodesPerAggregate) {
-                                        // aggList(aggSize) = neigh;
+                                         (aggStat(neigh) == READY) &&
+                                         (aggSize < maxNodesPerAggregate)) {
                                         ++aggSize;
                                       }
                                       ++numNeighbors;
@@ -152,26 +158,31 @@ namespace MueLu {
 
                                   // If a sufficient number of nodes can join the new aggregate
                                   // then we actually create the aggregate.
+                                  // Note on 2019-11-22, LBV:
+                                  // Same changes as described in the note above could be applied
                                   if(aggSize > minNodesPerAggregate &&
                                      aggSize > factor*numNeighbors) {
 
                                     // aggregates.SetIsRoot(rootCandidate);
                                     LO aggIndex = Kokkos::
                                       atomic_fetch_add(&numLocalAggregates(), 1);
 
-                                    for(int j = 0; j < neighbors.length; ++j) {
-                                      LO neigh = neighbors(j);
+                                    LO numAggregated = 0;
+                                    for(int neighIdx = 0; neighIdx < neighbors.length; ++neighIdx) {
+                                      LO neigh = neighbors(neighIdx);
                                       if(neigh != rootCandidate) {
                                         if(graph.isLocalNeighborVertex(neigh) &&
-                                           aggStat(neigh) == READY &&
-                                           aggSize < maxNodesPerAggregate) {
-                                          aggStat(neigh)   = AGGREGATED;
+                                           (aggStat(neigh) == READY) &&
+                                           (numAggregated < aggSize)) {
+                                          aggStat(neigh)         = AGGREGATED;
                                           vertex2AggId(neigh, 0) = aggIndex;
                                           procWinner(neigh, 0)   = myRank;
+
+                                          ++numAggregated;
+                                          --lNumNonAggregatedNodes;
                                         }
                                       }
                                     }
-                                    lNumNonAggregatedNodes -= aggSize;
                                   }
                                 }
                               }, tmpNumNonAggregatedNodes);

diff --git a/packages/muelu/test/interface/ParameterListInterpreter.cpp b/packages/muelu/test/interface/ParameterListInterpreter.cpp
@@ -407,6 +407,16 @@ int main_(Teuchos::CommandLineProcessor &clp, Xpetra::UnderlyingLib& lib, int ar
           stringToReplace = "Smoother complexity = " + floatRegex;
           replacementString = "Smoother complexity = <ignored>";
           run_sed("'s/" + stringToReplace + "/" + replacementString + "/'", baseFile);
+
+          // Finally ignore the Chebyshev eigen value ratio which varies with aggregation
+          stringToReplace = "chebyshev: ratio eigenvalue = " + floatRegex;
+          replacementString = "chebyshev: ratio eigenvalue = <ignored>";
+          run_sed("'s/" + stringToReplace + "/" + replacementString + "/'", baseFile);
+
+          // as well as the alpha paramter it sets
+          stringToReplace = "lambdaMax = <ignored>, alpha: " + floatRegex + ", lambdaMin = <ignored>,";
+          replacementString = "lambdaMax = <ignored>, alpha: <ignored>, lambdaMin = <ignored>,";
+          run_sed("'s/" + stringToReplace + "/" + replacementString + "/'", baseFile);
         }
 
         // Run comparison (ignoring whitespaces)