[telemetry] Add a V8GCTimes measurement and benchmarks.

tools/telemetry/telemetry/web_perf/metrics/fast_metric.py

-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-import logging
-
-from telemetry.timeline import bounds
-from telemetry.value import scalar
-from telemetry.web_perf import timeline_interaction_record as tir_module
-from telemetry.web_perf.metrics import timeline_based_metric
-from telemetry.web_perf.metrics import v8_stats as v8_stats_module
-
-
-class FastMetric(timeline_based_metric.TimelineBasedMetric):
-  def __init__(self):
-    super(FastMetric, self).__init__()
-
-  def AddResults(self, model, renderer_thread, interaction_records, results):
-    """Add 11 results: duration, cpu_time, and idle_time,
-                       incremental_marking, incremental_marking_outside_idle,
-                       scavenger, scavenger_outside_idle,
-                       mark_compactor, mark_compactor_outside_idle,
-                       total_garbage_collection,
-                       total_garbage_collection_outside_idle
-
-    duration is the total wall time for |interaction_records|.
-    cpu_time is the renderer thread time that intersects |interaction_records|.
-    idle time is wall time for |interaction_records| for which renderer slices
-        do not overlap. Note that unscheduled renderer thread time is not
-        counted. Idle time is time for which there was nothing to do.
-    incremental_marking is the total thread duration spent in incremental
-        marking steps.
-    incremental_marking_outside_idle is the thread duration spent in incremental
-        marking steps outside of idle notifications.
-    scavenger is the total thread duration spent in scavenges.
-    scavenger_outside_idle is the thread duration spent in scavenges outside of
-        idle notifications.
-    mark_compactor is the total thread duration spent in mark-sweep-compactor.
-    mark_compactor_outside_idle is the thread duration spent in
-        mark-sweep-compactor outside of idle notifications.
-    total_garbage_collection is the total thread duration spend in garbage
-        collection
-    total_garbage_collection_outside_idle is the total thread duration spend in
-        garbage collection outside of idle notification.
-
-    Args:
-      model: a TimelineModule instance
-      renderer_thread: a telemetry.timeline.thread.Thread() instance
-      interaction_records: an iterable of TimelineInteractionRecord instances
-      results: an instance of page.PageTestResults
-    """
-    self.VerifyNonOverlappedRecords(interaction_records)
-
-    duration = sum(r.end - r.start for r in interaction_records)
-    results.AddValue(scalar.ScalarValue(
-        results.current_page, 'fast-duration', 'ms', duration))
-
-    try:
-      cpu_time = sum(
-          r.GetOverlappedThreadTimeForSlice(s)
-          for r in interaction_records
-          for s in renderer_thread.toplevel_slices)
-    except tir_module.NoThreadTimeDataException:
-      logging.warning(
-          'Main thread cpu_time cannot be computed for records %s since '
-          'trace does not contain thread time data.',
-          repr(interaction_records))
-    else:
-      results.AddValue(scalar.ScalarValue(
-          results.current_page, 'fast-cpu_time', 'ms', cpu_time))
-
-    idle_time = duration - sum(
-        bounds.Bounds.GetOverlap(r.start, r.end, s.start, s.end)
-        for r in interaction_records
-        for s in renderer_thread.toplevel_slices)
-    results.AddValue(scalar.ScalarValue(
-        results.current_page, 'fast-idle_time', 'ms', idle_time))
-
-    v8_stats = v8_stats_module.V8Stats(renderer_thread, interaction_records)
-
-    for event_stats in v8_stats.all_event_stats:
-      results.AddValue(scalar.ScalarValue(
-          results.current_page, 'fast-' + event_stats.result_name, 'ms',
-          event_stats.thread_duration,
-          event_stats.result_description))
-      results.AddValue(scalar.ScalarValue(
-          results.current_page,
-          'fast-' + event_stats.result_name + '_outside_idle', 'ms',
-          event_stats.thread_duration_outside_idle,
-          event_stats.result_description + 'outside of idle notifications'))
-
-    results.AddValue(scalar.ScalarValue(
-        results.current_page, 'fast-total_garbage_collection', 'ms',
-        v8_stats.total_gc_thread_duration,
-        'Total thread duration of all garbage collection events'))
-
-    results.AddValue(scalar.ScalarValue(
-        results.current_page, 'fast-total_garbage_collection_outside_idle',
-        'ms', v8_stats.total_gc_thread_duration_outside_idle,
-        'Total thread duration of all garbage collection events outside of idle'
-        'notifications'))