algo: Add MemoryLogger to log memory usage of process.

algo/CMakeLists.txt

@@ -74,6 +74,8 @@ set(SRCS
   base/Options.cxx
   base/MainConfig.cxx
   base/RecoParams.cxx
+  base/System.cxx
+  base/util/MemoryLogger.cxx
   base/util/StlUtils.cxx
   base/util/EnumDict.cxx
   base/util/TimingsFormat.cxx
@@ -248,6 +250,7 @@ install(
     base/Options.h
     base/RecoParams.h
     base/SubChain.h
+    base/System.h
     base/PartitionedVector.h
     base/PartitionedSpan.h
     global/Reco.h

algo/base/System.cxx

+/* Copyright (C) 2024 FIAS Frankfurt Institute for Advanced Studies, Frankfurt / Main
+   SPDX-License-Identifier: GPL-3.0-only
+   Authors: Felix Weiglhofer [committer] */
+
+#include "System.h"
+
+#include <cstdio>
+
+#ifdef __linux__
+#include <sys/resource.h>
+#include <unistd.h>
+#endif
+
+
+size_t cbm::algo::GetCurrentRSS()
+{
+  // Implementation copied from https://stackoverflow.com/a/14927379
+#ifndef __linux__
+  return 0;
+#else
+  unsigned long rss = 0L;
+  FILE* fp          = nullptr;
+  if ((fp = fopen("/proc/self/statm", "r")) == nullptr) {
+    return size_t(0L); /* Can't open? */
+  }
+  if (fscanf(fp, "%*s%lu", &rss) != 1) {
+    fclose(fp);
+    return size_t(0L); /* Can't read? */
+  }
+  fclose(fp);
+  return size_t(rss) * size_t(sysconf(_SC_PAGESIZE));
+#endif
+}
+
+size_t cbm::algo::GetPeakRSS()
+{
+  // Implementation copied from https://stackoverflow.com/a/14927379
+#ifndef __linux__
+  return 0;
+#else
+  struct rusage rusage;
+  getrusage(RUSAGE_SELF, &rusage);
+
+  return size_t(rusage.ru_maxrss * 1024L);
+#endif
+}

algo/base/System.h

+/* Copyright (C) 2024 FIAS Frankfurt Institute for Advanced Studies, Frankfurt / Main
+   SPDX-License-Identifier: GPL-3.0-only
+   Authors: Felix Weiglhofer [committer] */
+
+#pragma once
+
+#include <cstddef>
+
+/**
+ * @file System.h
+ * @brief System functions
+**/
+
+namespace cbm::algo
+{
+
+  /**
+   * @brief Get the current resident set size (pyhysical memory usage) of the process
+   * @return The current resident set size in bytes
+   * @note Returns zero if the value cannot be determined
+  **/
+  size_t GetCurrentRSS();
+
+  /**
+   * @brief Get the peak resident set size (pyhysical memory usage) of the process
+   * @return The peak resident set size in bytes
+   * @note Returns zero if the value cannot be determined
+  **/
+  size_t GetPeakRSS();
+
+}  // namespace cbm::algo

algo/base/util/MemoryLogger.cxx

+/* Copyright (C) 2024 FIAS Frankfurt Institute for Advanced Studies, Frankfurt / Main
+   SPDX-License-Identifier: GPL-3.0-only
+   Authors: Felix Weiglhofer [committer] */
+
+#include "MemoryLogger.h"
+
+#include "System.h"
+
+#include <log.hpp>
+
+using namespace cbm::algo;
+
+template<typename T>
+T MemoryLogger::BytesToMB(T bytes) const
+{
+  return bytes / (1024 * 1024);
+}
+
+void MemoryLogger::Log()
+{
+  size_t currentRSS = GetCurrentRSS();
+  size_t peakRSS    = GetPeakRSS();
+
+  ptrdiff_t deltaRSS = currentRSS - mLastRSS;
+  float deltaPercent = 100.0f * deltaRSS / currentRSS;
+
+  L_(debug) << "Current memory usage: " << BytesToMB(currentRSS) << "MB (delta  " << BytesToMB(deltaRSS) << "MB / "
+            << deltaPercent << "%)"
+            << ", peak: " << BytesToMB(peakRSS) << "MB";
+
+  mLastRSS = currentRSS;
+}

algo/base/util/MemoryLogger.h

+/* Copyright (C) 2024 FIAS Frankfurt Institute for Advanced Studies, Frankfurt / Main
+   SPDX-License-Identifier: GPL-3.0-only
+   Authors: Felix Weiglhofer [committer] */
+
+#pragma once
+
+#include <cstddef>
+
+/**
+ * @file MemoryLogger.h
+ * @brief Memory logging
+**/
+
+namespace cbm::algo
+{
+
+  /**
+   * @brief Track the memory usage of the process and write it to the log
+  **/
+  class MemoryLogger {
+
+   public:
+    /**
+     * @brief Constructor
+    **/
+    MemoryLogger() = default;
+
+    /**
+     * @brief Destructor
+    **/
+    ~MemoryLogger() = default;
+
+    /**
+     * @brief Log the current memory usage
+    **/
+    void Log();
+
+   private:
+    size_t mLastRSS = 0;
+
+    // Convert bytes to MB
+    // Template to allow for different integer types
+    template<typename T>
+    T BytesToMB(T bytes) const;
+  };
+
+}  // namespace cbm::algo

reco/app/cbmreco/main.cxx

@@ -8,8 +8,10 @@
 #include "Reco.h"
 #include "RecoResultsInputArchive.h"
 #include "RecoResultsOutputArchive.h"
+#include "System.h"
 #include "compat/OpenMP.h"
 #include "gpu/DeviceImage.h"
+#include "util/MemoryLogger.h"
 
 #include <TimesliceAutoSource.hpp>
 
@@ -160,6 +162,7 @@ int main(int argc, char** argv)
   if (dumpArchive(opts)) return 0;
 
   Reco reco;
+  MemoryLogger memoryLogger;
 
   auto startProcessing = std::chrono::high_resolution_clock::now();
   reco.Init(opts);
@@ -198,6 +201,11 @@ int main(int argc, char** argv)
       L_(error) << "Caught ProcessingError while processing timeslice " << tsIdx << ": " << e.what();
     }
 
+    // Release memory after each timeslice and log memory usage
+    // This is useful to detect memory leaks as the memory usage should be constant between timeslices
+    ts.reset();
+    memoryLogger.Log();
+
     tsIdx++;
 
     if (num_ts > 0 && tsIdx >= num_ts) break;