1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
# Copyright 2013 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 random
import unittest
from metrics import smoothness
from metrics import statistics
from metrics import rendering_stats
from telemetry.core.backends.chrome.tracing_backend import RawTraceResultImpl
from telemetry.core.backends.chrome.trace_result import TraceResult
from telemetry.page import page
from telemetry.page.page_measurement_results import PageMeasurementResults
SYNTHETIC_GESTURE_MARKER = 'SyntheticGestureController::running'
class MockTimer(object):
"""A mock timer class which can generate random durations.
An instance of this class is used as a global timer to generate random
durations for stats and consistent timestamps for all mock trace events.
"""
def __init__(self):
self.microseconds = 0
def Advance(self, low=0, high=100000):
duration = random.randint(low, high)
self.microseconds += duration
return duration
class MockFrame(object):
"""Mocks rendering, texture and latency stats for a single frame."""
def __init__(self, mock_timer):
""" Initialize the stats to random values """
self.start = mock_timer.microseconds
self.main_stats = {}
self.impl_stats = {}
self.texture_stats = {}
self.latency_stats = {}
self.main_stats['frame_count'] = 0
self.main_stats['paint_time'] = mock_timer.Advance()
self.main_stats['painted_pixel_count'] = random.randint(0, 2000000)
self.main_stats['record_time'] = mock_timer.Advance()
self.main_stats['recorded_pixel_count'] = random.randint(0, 2000000)
self.impl_stats['frame_count'] = 1
self.impl_stats['rasterize_time'] = mock_timer.Advance()
self.impl_stats['rasterized_pixel_count'] = random.randint(0, 2000000)
self.end = mock_timer.microseconds
self.duration = self.end - self.start
def AppendTraceEventForMainThreadStats(self, trace_events):
"""Appends a trace event with the main thread stats.
The trace event is a dict with the following keys:
'name',
'tts' (thread timestamp),
'pid' (process id),
'ts' (timestamp),
'cat' (category),
'tid' (thread id),
'ph' (phase),
'args' (a dict with the key 'data').
This is related to src/base/debug/trace_event.h.
"""
event = {'name': 'MainThreadRenderingStats::IssueTraceEvent',
'tts': self.end,
'pid': 20978,
'ts': self.end,
'cat': 'benchmark',
's': 't',
'tid': 11,
'ph': 'i',
'args': {'data': self.main_stats}}
trace_events.append(event)
def AppendTraceEventForImplThreadStats(self, trace_events):
"""Appends a trace event with the impl thread stat."""
event = {'name': 'ImplThreadRenderingStats::IssueTraceEvent',
'tts': self.end,
'pid': 20978,
'ts': self.end,
'cat': 'benchmark',
's': 't',
'tid': 11,
'ph': 'i',
'args': {'data': self.impl_stats}}
trace_events.append(event)
class SmoothnessMetricUnitTest(unittest.TestCase):
def testCalcResultsTraceEvents(self):
# Make the test repeatable by seeding the random number generator
# (which is used by the mock timer) with a constant number.
random.seed(1234567)
mock_timer = MockTimer()
trace_events = []
total_time_seconds = 0.0
num_frames_sent = 0.0
first_frame = True
previous_frame_time = None
# This list represents time differences between frames in milliseconds.
expected_frame_times = []
# Append start trace events for the timeline marker and gesture marker,
# with some amount of time in between them.
trace_events.append({'name': rendering_stats.RENDER_PROCESS_MARKER,
'tts': mock_timer.microseconds,
'args': {},
'pid': 20978,
'ts': mock_timer.microseconds,
'cat': 'webkit',
'tid': 11,
'ph': 'S', # Phase: start.
'id': '0x12345'})
mock_timer.Advance()
trace_events.append({'name': SYNTHETIC_GESTURE_MARKER,
'tts': mock_timer.microseconds,
'args': {},
'pid': 20978,
'ts': mock_timer.microseconds,
'cat': 'webkit',
'tid': 11,
'ph': 'S',
'id': '0xabcde'})
# Generate 100 random mock frames and append their trace events.
for _ in xrange(0, 100):
mock_frame = MockFrame(mock_timer)
mock_frame.AppendTraceEventForMainThreadStats(trace_events)
mock_frame.AppendTraceEventForImplThreadStats(trace_events)
# Exclude the first frame, because it may have started before the
# benchmark run.
if not first_frame:
total_time_seconds += mock_frame.duration / 1e6
num_frames_sent += mock_frame.main_stats['frame_count']
num_frames_sent += mock_frame.impl_stats['frame_count']
first_frame = False
current_frame_time = mock_timer.microseconds / 1000.0
if previous_frame_time:
difference = current_frame_time - previous_frame_time
difference = round(difference, 2)
expected_frame_times.append(difference)
previous_frame_time = current_frame_time
# Append finish trace events for the timeline and gesture markers, in the
# reverse order from how they were added, with some time in between.
trace_events.append({'name': SYNTHETIC_GESTURE_MARKER,
'tts': mock_timer.microseconds,
'args': {},
'pid': 20978,
'ts': mock_timer.microseconds,
'cat': 'webkit',
'tid': 11,
'ph': 'F', # Phase: finish.
'id': '0xabcde'})
mock_timer.Advance()
trace_events.append({'name': rendering_stats.RENDER_PROCESS_MARKER,
'tts': mock_timer.microseconds,
'args': {},
'pid': 20978,
'ts': mock_timer.microseconds,
'cat': 'webkit',
'tid': 11,
'ph': 'F',
'id': '0x12345'})
# Create a timeline object from the trace.
trace_impl = RawTraceResultImpl(trace_events)
trace_result = TraceResult(trace_impl)
timeline = trace_result.AsTimelineModel()
# Find the timeline marker and gesture marker in the timeline,
# and create a RenderingStats object.
render_process_marker = timeline.FindTimelineMarkers(
rendering_stats.RENDER_PROCESS_MARKER)
timeline_markers = timeline.FindTimelineMarkers(
SYNTHETIC_GESTURE_MARKER)
stats = rendering_stats.RenderingStats(
render_process_marker, timeline_markers)
# Make a results object and add results to it from the smoothness metric.
results = PageMeasurementResults()
results.WillMeasurePage(page.Page('http://foo.com/', None))
smoothness_metric = smoothness.SmoothnessMetric(stats)
smoothness_metric.AddResults(None, results)
results.DidMeasurePage()
self.assertEquals(
expected_frame_times,
results.page_results[0]['frame_times'].value)
self.assertAlmostEquals(
1000.0 * (total_time_seconds / num_frames_sent),
results.page_results[0]['mean_frame_time'].value,
places=2)
# We don't verify the correctness of the discrepancy computation itself,
# because we have a separate unit test for that purpose.
self.assertAlmostEquals(
statistics.FrameDiscrepancy(stats.frame_timestamps, True),
results.page_results[0]['jank'].value,
places=4)
# We do not verify the correctness of Percentile here; Percentile should
# have its own test.
# The 17 here represents a threshold of 17 ms; this should match the value
# in the smoothness metric.
self.assertEquals(
statistics.Percentile(expected_frame_times, 95.0) < 17.0,
results.page_results[0]['mostly_smooth'].value)
|
