Telemetry: Add mean-frame-time and tasks-per-frame

tools/perf/metrics/timeline.py

Index: tools/perf/metrics/timeline.py
diff --git a/tools/perf/metrics/timeline.py b/tools/perf/metrics/timeline.py
index 19db3d59ad1985c1cebcc645f45719e60ae55cb0..6255285a61432832fb7d2171c2fece2ca288d61b 100644
--- a/tools/perf/metrics/timeline.py
+++ b/tools/perf/metrics/timeline.py
@@ -84,6 +84,12 @@ TimelineThreadCategories =  {
   "DummyThreadName3"      : "total_all"
 }
 
+# Normalizing cpu-time by different rates might get confusing, but we could
+# report different frame-rates by adding their associated trace here.

[ernstm, 2014/10/11 00:24:22]

Why add this if we don't use it? You could instead use FrameTraceThreadName and
FrameTraceName directly, no? If you want to keep it, I suggest changing variable
names, because having ThreadFrameTraceName, FrameTraceName and
FrameTraceThreadName is very confusing. This one could be called
FrameTraceMapping, becuase it maps FrameTraceThreadName to FrameTraceName.

[epenner, 2014/10/13 22:20:32]

Ahh, yeah my original goal was to remove those other ones and report multiple
frame-rates etc. but I decided not to do that. I've removed this mapping as we
can always add it in the future.

+ThreadFrameTraceName =  {
+  "renderer_compositor": "::SwapBuffers",
+}
+
 _MatchBySubString = ["IOThread", "CompositorRasterWorker"]
 
 AllThreads = TimelineThreadCategories.values()
@@ -103,6 +109,8 @@ OverheadTraceName = "overhead"
 FrameTraceName = "::SwapBuffers"
 FrameTraceThreadName = "renderer_compositor"
 
+def Rate(numerator, denominator):

[ernstm, 2014/10/11 00:24:22]

We have telmetry.util.statistics.DivideIfPossibleOrZero for this.

[epenner, 2014/10/13 22:20:32]

That doesn't cast to float. If you think I can change that to cast to float I'll
use it, otherwise I prefer keeping this.

[ernstm, 2014/10/14 17:06:11]

Please change DivideIfPossibleOrZero to cast to float. I only round one other
call site and that should definitely cast to float.

+  return (float(numerator) / denominator) if denominator else 0
 
 def ClockOverheadForEvent(event):
   if (event.category == OverheadTraceCategory and
@@ -127,12 +135,16 @@ def ThreadCategoryName(thread_name):
     thread_category = TimelineThreadCategories[thread_name]
   return thread_category
 
-def ThreadTimeResultName(thread_category):
-  return "thread_" + thread_category + "_clock_time_per_frame"
-
 def ThreadCpuTimeResultName(thread_category):
+  # This name sucks but I don't want to change it and lose continuity

[ernstm, 2014/10/11 00:24:22]

Metrics can be migrated to new names on the dashboard, if that helps.

[epenner, 2014/10/13 22:20:32]

That sounds cool. Got some documentation on that? How about I do it in a
separate patch. It will change many pagesets/benchmarks so I want to do it
carefully.

[ernstm, 2014/10/14 17:06:11]

qyearsley can help with the data migration. It is a good idea to do it as a
separate patch.

[epenner, 2014/10/18 01:02:30]

Acknowledged.

   return "thread_" + thread_category + "_cpu_time_per_frame"
 
+def ThreadTasksResultName(thread_category):
+  return "tasks_per_frame_" + thread_category
+
+def ThreadFpsResultName(thread_category):
+  return "fps_" + thread_category
+
 def ThreadDetailResultName(thread_category, detail):
   detail_sanitized = detail.replace('.','_')
   return "thread_" + thread_category + "|" + detail_sanitized
@@ -145,6 +157,8 @@ class ResultsForThread(object):
     self.all_slices = []
     self.name = name
     self.record_ranges = record_ranges
+    self.all_action_time = \
+        sum([record_range.bounds for record_range in self.record_ranges])
 
   @property
   def clock_time(self):
@@ -182,11 +196,23 @@ class ResultsForThread(object):
     self.all_slices.extend(self.SlicesInActions(thread.all_slices))
     self.toplevel_slices.extend(self.SlicesInActions(thread.toplevel_slices))
 
+  # Currently we report cpu-time per frame, tasks per frame, and possibly
+  # the frame rate (if there is a trace specified to find it).
   def AddResults(self, num_frames, results):
-    cpu_per_frame = (float(self.cpu_time) / num_frames) if num_frames else 0
+    cpu_per_frame = Rate(self.cpu_time, num_frames)
+    tasks_per_frame = Rate(len(self.toplevel_slices), num_frames)
     results.AddValue(scalar.ScalarValue(
         results.current_page, ThreadCpuTimeResultName(self.name),
         'ms', cpu_per_frame))
+    results.AddValue(scalar.ScalarValue(
+        results.current_page, ThreadTasksResultName(self.name),
+        'tasks', tasks_per_frame))
+    if self.name in ThreadFrameTraceName:
+      num_frames = self.CountTracesWithName(ThreadFrameTraceName[self.name])
+      frame_rate = Rate(num_frames, self.all_action_time) * 1000
+      results.AddValue(scalar.ScalarValue(
+          results.current_page, ThreadFpsResultName(self.name),
+          'fps', frame_rate))
 
   def AddDetailedResults(self, num_frames, results):
     slices_by_category = collections.defaultdict(list)
@@ -201,14 +227,18 @@ class ResultsForThread(object):
           results.current_page, ThreadDetailResultName(self.name, category),
           'ms', self_time_result))
     all_measured_time = sum(all_self_times)
-    all_action_time = \
-        sum([record_range.bounds for record_range in self.record_ranges])
-    idle_time = max(0, all_action_time - all_measured_time)
+    idle_time = max(0, self.all_action_time - all_measured_time)
     idle_time_result = (float(idle_time) / num_frames) if num_frames else 0
     results.AddValue(scalar.ScalarValue(
         results.current_page, ThreadDetailResultName(self.name, "idle"),
         'ms', idle_time_result))
 
+  def CountTracesWithName(self, substring):
+    count = 0
+    for event in self.all_slices:
+      if substring in event.name:
+        count += 1
+    return count
 
 class ThreadTimesTimelineMetric(timeline_based_metric.TimelineBasedMetric):
   def __init__(self):
@@ -217,13 +247,6 @@ class ThreadTimesTimelineMetric(timeline_based_metric.TimelineBasedMetric):
     self.results_to_report = AllThreads
     self.details_to_report = NoThreads
 
-  def CountSlices(self, slices, substring):
-    count = 0
-    for event in slices:
-      if substring in event.name:
-        count += 1
-    return count
-
   def AddResults(self, model, _, interaction_records, results):
     # Set up each thread category for consistant results.
     thread_category_results = {}
@@ -245,9 +268,9 @@ class ThreadTimesTimelineMetric(timeline_based_metric.TimelineBasedMetric):
       if ThreadCategoryName(thread.name) in FastPathThreads:
         thread_category_results['total_fast_path'].AppendThreadSlices(thread)
 
-    # Calculate the number of frames.
-    frame_slices = thread_category_results[FrameTraceThreadName].all_slices
-    num_frames = self.CountSlices(frame_slices, FrameTraceName)
+    # Calculate the number of frames / frame-rate.
+    frame_rate_thread = thread_category_results[FrameTraceThreadName]
+    num_frames = frame_rate_thread.CountTracesWithName(FrameTraceName)
 
     # Report the desired results and details.
     for thread_results in thread_category_results.values():