ITS: create artefacts labels only on demand (#14594)

Author: f3sch

Detectors/ITSMFT/ITS/tracking/include/ITStracking/Configuration.h

@@ -80,6 +80,8 @@ struct TrackingParameters {
   float TrackFollowerNSigmaCutZ = 1.f;
   float TrackFollowerNSigmaCutPhi = 1.f;
 
+  bool createArtefactLabels{false};
+
   bool PrintMemory = false; // print allocator usage in epilog report
   size_t MaxMemory = std::numeric_limits<size_t>::max();
   bool DropTFUponFailure = false;

Detectors/ITSMFT/ITS/tracking/include/ITStracking/TrackingConfigParam.h

@@ -97,6 +97,8 @@ struct TrackerParamConfig : public o2::conf::ConfigurableParamHelper<TrackerPara
   bool doUPCIteration = false;             // Perform an additional iteration for UPC events on tagged vertices. You want to combine this config with VertexerParamConfig.nIterations=2
   int nIterations = MaxIter;               // overwrite the number of iterations
 
+  bool createArtefactLabels{false}; // create on-the-fly labels for the artefacts
+
   int nThreads = 1;
   bool printMemory = false;
   size_t maxMemory = std::numeric_limits<size_t>::max();

Detectors/ITSMFT/ITS/tracking/src/Configuration.cxx

@@ -187,6 +187,8 @@ std::vector<TrackingParameters> TrackingMode::getTrackingParameters(TrackingMode
       p.MinPt[lslot] *= bFactor;
     }
 
+    p.createArtefactLabels = tc.createArtefactLabels;
+
     p.PrintMemory = tc.printMemory;
     p.MaxMemory = tc.maxMemory;
     p.DropTFUponFailure = tc.dropTFUponFailure;

Detectors/ITSMFT/ITS/tracking/src/TimeFrame.cxx

@@ -666,7 +666,6 @@ void TimeFrame<nLayers>::wipe()
   deepVectorClear(mROFramesPV);
   deepVectorClear(mPrimaryVertices);
   deepVectorClear(mRoads);
-  deepVectorClear(mRoadLabels);
   deepVectorClear(mMSangles);
   deepVectorClear(mPhiCuts);
   deepVectorClear(mPositionResolution);
@@ -676,9 +675,15 @@ void TimeFrame<nLayers>::wipe()
   deepVectorClear(mTrackletsIndexROF);
   deepVectorClear(mPrimaryVertices);
   deepVectorClear(mTrackletClusters);
-  deepVectorClear(mVerticesContributorLabels);
   deepVectorClear(mLines);
-  deepVectorClear(mLinesLabels);
+  if (hasMCinformation()) {
+    deepVectorClear(mLinesLabels);
+    deepVectorClear(mVerticesContributorLabels);
+    deepVectorClear(mTrackletLabels);
+    deepVectorClear(mCellLabels);
+    deepVectorClear(mRoadLabels);
+    deepVectorClear(mTracksLabel);
+  }
 }
 
 template class TimeFrame<7>;

Detectors/ITSMFT/ITS/tracking/src/TrackerTraits.cxx

@@ -272,7 +272,7 @@ void TrackerTraits<nLayers>::computeLayerTracklets(const int iteration, int iROF
       });
 
     /// Create tracklets labels
-    if (mTimeFrame->hasMCinformation()) {
+    if (mTimeFrame->hasMCinformation() && mTrkParams[iteration].createArtefactLabels) {
       tbb::parallel_for(
         tbb::blocked_range<int>(0, mTrkParams[iteration].TrackletsPerRoad()),
         [&](const tbb::blocked_range<int>& Layers) {
@@ -313,7 +313,7 @@ void TrackerTraits<nLayers>::computeLayerCells(const int iteration)
     if (iLayer > 0) {
       deepVectorClear(mTimeFrame->getCellsLookupTable()[iLayer - 1]);
     }
-    if (mTimeFrame->hasMCinformation()) {
+    if (mTimeFrame->hasMCinformation() && mTrkParams[iteration].createArtefactLabels) {
       deepVectorClear(mTimeFrame->getCellsLabel(iLayer));
     }
   }
@@ -458,14 +458,19 @@ void TrackerTraits<nLayers>::computeLayerCells(const int iteration)
   });
 
   /// Create cells labels
-  if (mTimeFrame->hasMCinformation()) {
-    for (int iLayer{0}; iLayer < mTrkParams[iteration].CellsPerRoad(); ++iLayer) {
-      for (const auto& cell : mTimeFrame->getCells()[iLayer]) {
-        MCCompLabel currentLab{mTimeFrame->getTrackletsLabel(iLayer)[cell.getFirstTrackletIndex()]};
-        MCCompLabel nextLab{mTimeFrame->getTrackletsLabel(iLayer + 1)[cell.getSecondTrackletIndex()]};
-        mTimeFrame->getCellsLabel(iLayer).emplace_back(currentLab == nextLab ? currentLab : MCCompLabel());
-      }
-    }
+  if (mTimeFrame->hasMCinformation() && mTrkParams[iteration].createArtefactLabels) {
+    tbb::parallel_for(
+      tbb::blocked_range<int>(0, mTrkParams[iteration].CellsPerRoad()),
+      [&](const tbb::blocked_range<int>& Layers) {
+        for (int iLayer = Layers.begin(); iLayer < Layers.end(); ++iLayer) {
+          mTimeFrame->getCellsLabel(iLayer).reserve(mTimeFrame->getCells()[iLayer].size());
+          for (const auto& cell : mTimeFrame->getCells()[iLayer]) {
+            MCCompLabel currentLab{mTimeFrame->getTrackletsLabel(iLayer)[cell.getFirstTrackletIndex()]};
+            MCCompLabel nextLab{mTimeFrame->getTrackletsLabel(iLayer + 1)[cell.getSecondTrackletIndex()]};
+            mTimeFrame->getCellsLabel(iLayer).emplace_back(currentLab == nextLab ? currentLab : MCCompLabel());
+          }
+        }
+      });
   }
 }