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
|
-- Copyright 2023 The Chromium Authors
-- Use of this source code is governed by a BSD-style license that can be
-- found in the LICENSE file.
--- sqlformat file off
-- This file creates two public views:
-- - chrome_scroll_input_offsets and
-- - chrome_presented_scroll_offsets
--
-- These views store the pixel deltas and offsets for (respectively) all chrome
-- scroll inputs (coalesced and not coalesced), and for chrome presented frames
-- (not coalesced), along with the associated timestamp, and id.
--
-- Raw deltas are recorded as changes in pixel positions along the y-axis of a
-- screen, and are scaled to the viewport size. The corresponding trace event
-- for this is TranslateAndScaleWebInputEvent. These are the deltas for all
-- chrome scroll inputs.
--
-- For presented frames, the delta is calculated from the visual offset,
-- recorded once the input has been processed, in the
-- InputHandlerProxy::HandleGestureScrollUpdate_Result event. These values are
-- also scaled to the screen size.
--
-- Offsets are calculated by summing all of the deltas, ordered by timestamp.
-- For a given input/frame, the offset is the sum of its corresponding delta and
-- all previous deltas.
--
--
-- All values required for calculating deltas and offsets are recorded at
-- various stages of input processing, and are unified by a single
-- scroll_update_id value, recorded as scroll_deltas.trace_id in each event.
INCLUDE PERFETTO MODULE chrome.event_latency;
-- The raw input deltas for all input events which were part of a scroll.
CREATE PERFETTO TABLE chrome_scroll_input_deltas(
-- Scroll update id (aka LatencyInfo.ID) for this scroll update input
-- event.
scroll_update_id LONG,
-- The delta in pixels (scaled to the device's screen size) how much this
-- input event moved over the X axis vs previous, as reported by the OS.
delta_x DOUBLE,
-- The delta in pixels (scaled to the device's screen size) how much this
-- input event moved over the Y axis vs previous, as reported by the OS.
delta_y DOUBLE
) AS
SELECT
EXTRACT_ARG(arg_set_id, 'scroll_deltas.trace_id') AS scroll_update_id,
EXTRACT_ARG(arg_set_id, 'scroll_deltas.original_delta_x') AS delta_x,
EXTRACT_ARG(arg_set_id, 'scroll_deltas.original_delta_y') AS delta_y
FROM slice
WHERE slice.name = 'TranslateAndScaleWebInputEvent';
-- The raw coordinates and pixel offsets for all input events which were part of
-- a scroll.
CREATE PERFETTO TABLE chrome_scroll_input_offsets(
-- An ID for this scroll update (aka LatencyInfo.ID).
scroll_update_id LONG,
-- An ID for the scroll this scroll update belongs to.
scroll_id LONG,
-- Timestamp the of the scroll input event.
ts TIMESTAMP,
-- The delta in raw coordinates between this scroll update event and the
-- previous.
delta_y DOUBLE,
-- The total delta of all scroll updates within the same as scroll up to and
-- including this scroll update.
relative_offset_y DOUBLE
) AS
SELECT
delta.scroll_update_id,
scroll_update.scroll_id,
ts,
delta_y,
SUM(delta_y) OVER (
PARTITION BY scroll_id
ORDER BY ts
ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW
) AS relative_offset_y
FROM chrome_scroll_input_deltas delta
JOIN chrome_gesture_scroll_updates scroll_update USING (scroll_update_id);
-- The page offset delta (by how much the page was scrolled vs previous frame)
-- for each frame.
-- This is the resulting delta that is shown to the user after the input has
-- been processed. `chrome_scroll_input_deltas` tracks the underlying signal
-- deltas between consecutive input events.
CREATE PERFETTO TABLE chrome_scroll_presented_deltas(
-- Scroll update id (aka LatencyInfo.ID) for this scroll update input
-- event.
scroll_update_id LONG,
-- The delta in pixels (scaled to the device's screen size) how much this
-- input event moved over the X axis vs previous, as reported by the OS.
delta_x DOUBLE,
-- The delta in pixels (scaled to the device's screen size) how much this
-- input event moved over the Y axis vs previous, as reported by the OS.
delta_y DOUBLE,
-- The page offset in pixels (scaled to the device's screen size) along
-- the X axis.
offset_x LONG,
-- The page offset in pixels (scaled to the device's screen size) along
-- the Y axis.
offset_y LONG
) AS
SELECT
EXTRACT_ARG(arg_set_id, 'scroll_deltas.trace_id') AS scroll_update_id,
EXTRACT_ARG(arg_set_id, 'scroll_deltas.provided_to_compositor_delta_x') AS delta_x,
EXTRACT_ARG(arg_set_id, 'scroll_deltas.provided_to_compositor_delta_y') AS delta_y,
EXTRACT_ARG(arg_set_id, 'scroll_deltas.visual_offset_x') AS offset_x,
EXTRACT_ARG(arg_set_id, 'scroll_deltas.visual_offset_y') AS offset_y
FROM slice
WHERE slice.name = 'InputHandlerProxy::HandleGestureScrollUpdate_Result';
-- The scrolling offsets for the actual (applied) scroll events. These are not
-- necessarily inclusive of all user scroll events, rather those scroll events
-- that are actually processed.
CREATE PERFETTO TABLE chrome_presented_scroll_offsets(
-- An ID for this scroll update (aka LatencyInfo.ID).
scroll_update_id LONG,
-- An ID for the scroll this scroll update belongs to.
scroll_id LONG,
-- Presentation timestamp.
ts TIMESTAMP,
-- The delta in raw coordinates between this scroll update event and the
-- previous.
delta_y DOUBLE,
-- The pixel offset of this scroll update event compared to the initial one.
relative_offset_y DOUBLE
) AS
WITH data AS (
SELECT
scroll_update_id,
scroll_id,
presentation_timestamp AS ts,
-- Aggregate the deltas for each presentation time.
SUM(delta_y) OVER (PARTITION BY presentation_timestamp) AS delta_y,
SUM(delta_y) OVER (
PARTITION BY scroll_id
ORDER BY presentation_timestamp
GROUPS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW
) AS relative_offset_y,
-- For each presentation time, select the last scroll update as there can
-- be multiple EventLatencies with the same presentation time.
ROW_NUMBER() OVER (
PARTITION BY presentation_timestamp
ORDER BY scroll_update.ts
) AS rank
FROM chrome_scroll_presented_deltas
JOIN chrome_gesture_scroll_updates scroll_update USING (scroll_update_id)
)
SELECT
scroll_update_id,
scroll_id,
ts,
delta_y,
relative_offset_y
FROM data
WHERE rank = 1;
|
