From a287b79d886398f04f8129bfa9729db66d0fbafc Mon Sep 17 00:00:00 2001
From: Felice <felice.pantaleo@cern.ch>
Date: Thu, 16 Jul 2020 18:12:57 +0200
Subject: [PATCH] Shrinking internal data structures after clearing them.

---
 .../interface/HGCalImagingAlgo.h              |  3 +++
 .../HGCalRecProducers/plugins/HGCalCLUEAlgo.h | 22 ++++++++++++++++++-
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/RecoLocalCalo/HGCalRecProducers/interface/HGCalImagingAlgo.h b/RecoLocalCalo/HGCalRecProducers/interface/HGCalImagingAlgo.h
index 6d7e2dd900265..ba072a85de7fd 100644
--- a/RecoLocalCalo/HGCalRecProducers/interface/HGCalImagingAlgo.h
+++ b/RecoLocalCalo/HGCalRecProducers/interface/HGCalImagingAlgo.h
@@ -65,9 +65,12 @@ class HGCalImagingAlgo : public HGCalClusteringAlgoBase {
   // use this if you want to reuse the same cluster object but don't want to accumulate clusters (hardly useful?)
   void reset() override {
     clusters_v_.clear();
+    clusters_v_.shrink_to_fit();
     layerClustersPerLayer_.clear();
+    layerClustersPerLayer_.shrink_to_fit();
     for (auto &it : points_) {
       it.clear();
+      it.shrink_to_fit();
       std::vector<KDNode>().swap(it);
     }
     for (unsigned int i = 0; i < minpos_.size(); i++) {
diff --git a/RecoLocalCalo/HGCalRecProducers/plugins/HGCalCLUEAlgo.h b/RecoLocalCalo/HGCalRecProducers/plugins/HGCalCLUEAlgo.h
index caf5faee1e374..861447e874b0c 100644
--- a/RecoLocalCalo/HGCalRecProducers/plugins/HGCalCLUEAlgo.h
+++ b/RecoLocalCalo/HGCalRecProducers/plugins/HGCalCLUEAlgo.h
@@ -63,12 +63,15 @@ class HGCalCLUEAlgoT : public HGCalClusteringAlgoBase {
 
   void reset() override {
     clusters_v_.clear();
+    clusters_v_.shrink_to_fit();
     for (auto& cl : numberOfClustersPerLayer_) {
       cl = 0;
     }
 
-    for (auto& cells : cells_)
+    for (auto& cells : cells_) {
       cells.clear();
+      cells.shrink_to_fit();
+    }
   }
 
   Density getDensity() override;
@@ -174,6 +177,23 @@ class HGCalCLUEAlgoT : public HGCalClusteringAlgoBase {
       followers.clear();
       isSeed.clear();
     }
+
+    void shrink_to_fit() {
+      detid.shrink_to_fit();
+      isSi.shrink_to_fit();
+      x.shrink_to_fit();
+      y.shrink_to_fit();
+      eta.shrink_to_fit();
+      phi.shrink_to_fit();
+      weight.shrink_to_fit();
+      rho.shrink_to_fit();
+      delta.shrink_to_fit();
+      nearestHigher.shrink_to_fit();
+      clusterIndex.shrink_to_fit();
+      sigmaNoise.shrink_to_fit();
+      followers.shrink_to_fit();
+      isSeed.shrink_to_fit();
+    }
   };
 
   std::vector<CellsOnLayer> cells_;