Merge branch '21.1-zf' into '21.1'

Fix hang due to unfortunate convergence of input settings

See merge request atlas/athena!20329

Trigger/TrigTools/IDScanZFinder/IDScanZFinder/TrigZFinderInternal.h

@@ -18,8 +18,8 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 
-#ifndef __TRIGZFINDERINTERNAL_H__
-#define __TRIGZFINDERINTERNAL_H__
+#ifndef TRIGZFINDERINTERNAL_H
+#define TRIGZFINDERINTERNAL_H
 
 #include <cmath>
 #include <vector>

Trigger/TrigTools/IDScanZFinder/src/TrigZFinderInternal.cxx

@@ -639,7 +639,7 @@ std::vector<typename TrigZFinderInternal::vertex>* TrigZFinderInternal::findZInt
 			       zHisto[bending][bestPhi][binMax-1] ) /maxh;
 	
         /// if found a vertex flag the bins so we don't use them again 
-        if ( m_numberOfPeaks>1 ) { 
+        if ( m_numberOfPeaks>0 ) { 
           nHisto[bending][bestPhi][binMax]   = -1;
           nHisto[bending][bestPhi][binMax-1] = -1;
           nHisto[bending][bestPhi][binMax+1] = -1;
@@ -669,7 +669,7 @@ std::vector<typename TrigZFinderInternal::vertex>* TrigZFinderInternal::findZInt
 	  double significance = 0;
 	  if ( bg>0 ) { 
 	    significance = (maxh-bg)/std::sqrt(bg);
-	    if ( significance < m_minVtxSignificance ) addvtx = false;
+	    if ( significance < m_minVtxSignificance ) break; // if this vertex is not significant then no subsequent vertex could be either  
 	  }
 
 	  if ( addvtx ) {