Add perfetto track counters to accel LocalTransporter (#1634)

celeritas-project · Feb 21, 2025 · 6cd2f98 · 6cd2f98
1 parent caeafdb
commit 6cd2f98
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Showing 4 changed files with 75 additions and 6 deletions.
diff --git a/src/accel/LocalTransporter.cc b/src/accel/LocalTransporter.cc
@@ -28,13 +28,17 @@
 #include "corecel/io/Logger.hh"
 #include "corecel/sys/Device.hh"
 #include "corecel/sys/Environment.hh"
+#include "corecel/sys/ScopedProfiling.hh"
 #include "corecel/sys/ScopedSignalHandler.hh"
+#include "corecel/sys/TraceCounter.hh"
+#include "corecel/sys/TracingSession.hh"
 #include "geocel/GeantUtils.hh"
 #include "geocel/g4/Convert.hh"
 #include "celeritas/Quantities.hh"
 #include "celeritas/ext/GeantSd.hh"
 #include "celeritas/ext/GeantUnits.hh"
 #include "celeritas/global/ActionSequence.hh"
+#include "celeritas/global/Stepper.hh"
 #include "celeritas/io/EventWriter.hh"
 #include "celeritas/io/RootEventWriter.hh"
 #include "celeritas/phys/PDGNumber.hh"
@@ -58,6 +62,45 @@ bool nonfatal_flush()
     return result;
 }
 
+//---------------------------------------------------------------------------//
+//! Trace the number of active, alive, dead, and queued tracks
+class TrackCounters
+{
+  public:
+    TrackCounters()
+    {
+        if (use_profiling())
+        {
+            std::string stream_id = std::to_string(get_geant_thread_id());
+            active_counter_ = std::string("active-" + stream_id);
+            alive_counter_ = std::string("alive-" + stream_id);
+            dead_counter_ = std::string("dead-" + stream_id);
+            queued_counter_ = std::string("queued-" + stream_id);
+        }
+    };
+
+    void operator()(StepperResult const& track_counts) const
+    {
+        trace_counter(active_counter_.c_str(), track_counts.active);
+        trace_counter(alive_counter_.c_str(), track_counts.alive);
+        trace_counter(dead_counter_.c_str(),
+                      track_counts.active - track_counts.alive);
+        trace_counter(queued_counter_.c_str(), track_counts.queued);
+    }
+
+  private:
+    std::string active_counter_;
+    std::string alive_counter_;
+    std::string dead_counter_;
+    std::string queued_counter_;
+};
+
+void trace(StepperResult const& track_counts)
+{
+    static thread_local TrackCounters const trace_;
+    trace_(track_counts);
+}
+
 #define CELER_VALIDATE_OR_KILL_ACTIVE(COND, MSG, STEPPER)           \
     do                                                              \
     {                                                               \
@@ -321,6 +364,7 @@ void LocalTransporter::Flush()
     run_accum_.steps += track_counts.active;
     run_accum_.primaries += buffer_.size();
     run_accum_.lost_primaries += buffer_accum_.lost_primaries;
+    trace(track_counts);
 
     buffer_.clear();
     buffer_accum_ = {};
@@ -338,7 +382,7 @@ void LocalTransporter::Flush()
         track_counts = (*step_)();
         run_accum_.steps += track_counts.active;
         ++step_iters;
-
+        trace(track_counts);
         CELER_VALIDATE_OR_KILL_ACTIVE(
             !interrupted(), << "caught interrupt signal", *step_);
     }
@@ -382,6 +426,9 @@ void LocalTransporter::Finalize()
 #endif
     }
 
+    // Flush any remaining track counters on the worker thread
+    flush_tracing();
+
     // Reset all data
     CELER_LOG_LOCAL(debug) << "Resetting local transporter";
     *this = {};

diff --git a/src/corecel/sys/TraceCounter.perfetto.cc b/src/corecel/sys/TraceCounter.perfetto.cc
@@ -11,6 +11,7 @@
 #include <perfetto.h>
 
 #include "corecel/Types.hh"
+#include "corecel/sys/ScopedProfiling.hh"
 
 #include "detail/TrackEvent.perfetto.hh"
 
@@ -31,9 +32,12 @@ template<class T>
 void trace_counter(char const* name, T value)
 {
     static_assert(std::is_arithmetic_v<T>, "Only support numeric counters");
-    TRACE_COUNTER(detail::perfetto_track_event_category,
-                  ::perfetto::DynamicString{name},
-                  value);
+    if (use_profiling())
+    {
+        TRACE_COUNTER(detail::perfetto_track_event_category,
+                      ::perfetto::DynamicString{name},
+                      value);
+    }
 }
 
 //---------------------------------------------------------------------------//

diff --git a/src/corecel/sys/TracingSession.cc b/src/corecel/sys/TracingSession.cc
@@ -86,6 +86,20 @@ perfetto::TraceConfig configure_session() noexcept
 //---------------------------------------------------------------------------//
 }  // namespace
 
+//---------------------------------------------------------------------------//
+/*!
+ * Perform the same action a \c TracingSession::flush, however, it does not
+ * require a session instance. This is useful in geant4 applications, where
+ * workers do not have access to the session instance.
+ */
+void flush_tracing() noexcept
+{
+    if (use_profiling())
+    {
+        perfetto::TrackEvent::Flush();
+    }
+}
+
 //---------------------------------------------------------------------------//
 /*!
  * Start a system tracing session.
@@ -162,7 +176,7 @@ void TracingSession::flush() noexcept
 {
     if (session_ && started_)
     {
-        perfetto::TrackEvent::Flush();
+        flush_tracing();
     }
 }
 

diff --git a/src/corecel/sys/TracingSession.hh b/src/corecel/sys/TracingSession.hh
@@ -21,6 +21,10 @@ class TracingSession;
 
 namespace celeritas
 {
+//---------------------------------------------------------------------------//
+// Flush perfetto track events without requiring a TracingSession instance.
+void flush_tracing() noexcept;
+
 //---------------------------------------------------------------------------//
 /*!
  * RAII wrapper for a tracing session.
@@ -79,7 +83,7 @@ class TracingSession
 //---------------------------------------------------------------------------//
 
 #if !CELERITAS_USE_PERFETTO
-
+inline void flush_tracing() noexcept {}
 inline TracingSession::TracingSession() noexcept = default;
 inline TracingSession::TracingSession(std::string_view) noexcept {}
 inline TracingSession::~TracingSession() = default;