TrigOnlineMonitor: Add histograms to monitor number of forks, threads and slots

HLT/Trigger/TrigMonitoring/TrigOnlineMonitor/src/TrigOpMonitor.cxx

@@ -76,6 +76,8 @@ void TrigOpMonitor::handle( const Incident& incident ) {
     fillMagFieldHist();
     fillIOVDbHist();
     fillSubDetHist();
+    const AthenaInterprocess::UpdateAfterFork& updinc = dynamic_cast<const AthenaInterprocess::UpdateAfterFork&>(incident);
+    fillProcThreadHist(updinc.workerID());
   }
 }
 
@@ -128,6 +130,14 @@ StatusCode TrigOpMonitor::bookHists()
 
   m_releaseHist = new TH1I("GeneralOpInfo", "General operational info;;Applications", 1, 0, 1);
 
+  m_mtConfigHist = new TH2I("MTConfig", "Multi-threading configuration", 2, 0, 2, 10, 0, 10);
+  m_mtConfigHist->SetCanExtend(TH1::kYaxis);
+  m_mtConfigHist->GetXaxis()->SetBinLabel(1, "N threads");
+  m_mtConfigHist->GetXaxis()->SetBinLabel(2, "N slots");
+
+  m_workersHist = new TH1I("MPWorkers", "Worker IDs;Worker ID;Number of workers", 10, 0, 10);
+  m_workersHist->SetCanExtend(TH1::kXaxis);
+
   m_subdetHist = new TH2I("Subdetectors", "State of subdetectors", 1, 0, 1, 3, 0, 3);
   m_subdetHist->SetCanExtend(TH1::kXaxis);
   m_subdetHist->GetYaxis()->SetBinLabel(1, "# ROB");
@@ -140,7 +150,10 @@ StatusCode TrigOpMonitor::bookHists()
   m_muHist = new TProfile("Pileup", "Pileup;Lumiblock;Interactions per BX", m_maxLB, 0, m_maxLB);
 
   // Register histograms
-  TH1* hist[] = {m_releaseHist, m_subdetHist, m_iovChangeHist, m_magFieldHist, m_lumiHist, m_muHist};
+  TH1* hist[] = {
+    m_releaseHist, m_mtConfigHist, m_workersHist, m_subdetHist,
+    m_iovChangeHist, m_magFieldHist, m_lumiHist, m_muHist
+  };
   for (TH1* h : hist) {
     if (h) ATH_CHECK(m_histSvc->regHist(m_histPath + h->GetName(), h));
   }
@@ -347,6 +360,38 @@ void TrigOpMonitor::fillReleaseDataHist()
   }
 }
 
+void TrigOpMonitor::fillProcThreadHist(const int workerID)
+{
+  m_workersHist->Fill(workerID, 1);
+
+  auto getIntProp = [this](std::string_view name, const std::string& prop) -> std::optional<int> {
+    IProperty* svc = serviceLocator()->service(name).as<IProperty>();
+    if (svc == nullptr) return std::nullopt;
+    try {
+      return std::stoi(svc->getProperty(prop).toString());
+    }
+    catch (...) {
+      return std::nullopt;
+    }
+  };
+
+  const std::optional<int> numThreads = getIntProp("AvalancheSchedulerSvc","ThreadPoolSize");
+  if (numThreads.has_value()) {
+    m_mtConfigHist->Fill("N threads", numThreads.value(), 1.0);
+  }
+  else {
+    ATH_MSG_WARNING("Could not retrieve the number of threads to fill the monitoring histogram");
+  }
+
+  const std::optional<int> numSlots = getIntProp("EventDataSvc","NSlots");
+  if (numSlots.has_value()) {
+    m_mtConfigHist->Fill("N slots", numSlots.value(), 1.0);
+  }
+  else {
+    ATH_MSG_WARNING("Could not retrieve the number of slots to fill the monitoring histogram");
+  }
+}
+
 void TrigOpMonitor::fillSubDetHist()
 {
   // Retrieve the enabled ROBs/SubDets list from DataFlowConfig which is a special object

HLT/Trigger/TrigMonitoring/TrigOnlineMonitor/src/TrigOpMonitor.h

@@ -51,6 +51,7 @@ public:
 private:
   void fillMagFieldHist();
   void fillReleaseDataHist();
+  void fillProcThreadHist(int workerID);
   void fillSubDetHist();
   void fillIOVDbHist();
   void fillIOVDbChangeHist(const EventContext& ctx);
@@ -75,6 +76,8 @@ private:
   TH2I* m_magFieldHist{nullptr};
   TH2I* m_iovChangeHist{nullptr};
   TH1I* m_releaseHist{nullptr};
+  TH2I* m_mtConfigHist{nullptr};
+  TH1I* m_workersHist{nullptr};
   TH2I* m_subdetHist{nullptr};
   TProfile* m_lumiHist{nullptr};
   TProfile* m_muHist{nullptr};