Cycles: add time statistics to scene update

Gathers information for time spent in the various managers or object (Film, Camera, etc.) being updated in Scene::device_update.

The stats include the total time spent in the device_update methods as well as time spent in subroutines (e.g. bvh build, displacement, etc.).

This does not qualify as a full blown profiler, but is useful to identify potential bottleneck areas.

The stats can be enabled and printed by passing `--cycles-print-stats` on the command line to Cycles, or `-- --cycles-print-stats` to Blender.

Reviewed By: brecht

Maniphest Tasks: T79174

Differential Revision: https://developer.blender.org/D8596

1 files changed, 64 insertions, 0 deletions

diff --git a/intern/cycles/render/stats.h b/intern/cycles/render/stats.h
index e45403a3754..5dca6dd0b01 100644
--- a/intern/cycles/render/stats.h
+++ b/intern/cycles/render/stats.h
@@ -41,6 +41,15 @@ class NamedSizeEntry {
   size_t size;
 };
 
+class NamedTimeEntry {
+ public:
+  NamedTimeEntry();
+  NamedTimeEntry(const string &name, double time);
+
+  string name;
+  double time;
+};
+
 /* Container of named size entries. Used, for example, to store per-mesh memory
  * usage statistics. But also keeps track of overall memory usage of the
  * container.
@@ -64,6 +73,29 @@ class NamedSizeStats {
   vector<NamedSizeEntry> entries;
 };
 
+class NamedTimeStats {
+ public:
+  NamedTimeStats();
+
+  /* Add entry to the statistics. */
+  void add_entry(const NamedTimeEntry &entry)
+  {
+    total_time += entry.time;
+    entries.push_back(entry);
+  }
+
+  /* Generate full human-readable report. */
+  string full_report(int indent_level = 0);
+
+  /* Total time of all entries. */
+  double total_time;
+
+  /* NOTE: Is fine to read directly, but for adding use add_entry(), which
+   * makes sure all accumulating  values are properly updated.
+   */
+  vector<NamedTimeEntry> entries;
+};
+
 class NamedNestedSampleStats {
  public:
   NamedNestedSampleStats();
@@ -155,6 +187,38 @@ class RenderStats {
   NamedSampleCountStats objects;
 };
 
+class UpdateTimeStats {
+ public:
+  /* Generate full human-readable report. */
+  string full_report(int indent_level = 0);
+
+  NamedTimeStats times;
+};
+
+class SceneUpdateStats {
+ public:
+  SceneUpdateStats();
+
+  UpdateTimeStats geometry;
+  UpdateTimeStats image;
+  UpdateTimeStats light;
+  UpdateTimeStats object;
+  UpdateTimeStats background;
+  UpdateTimeStats bake;
+  UpdateTimeStats camera;
+  UpdateTimeStats film;
+  UpdateTimeStats integrator;
+  UpdateTimeStats osl;
+  UpdateTimeStats particles;
+  UpdateTimeStats scene;
+  UpdateTimeStats svm;
+  UpdateTimeStats tables;
+
+  string full_report();
+
+  void clear();
+};
+
 CCL_NAMESPACE_END
 
 #endif /* __RENDER_STATS_H__ */