-- 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.
-- Source of truth of the descriptions of EventLatency stages.
CREATE PERFETTO TABLE chrome_event_latency_stage_descriptions (
-- The name of the EventLatency stage.
name STRING,
-- A description of the EventLatency stage.
description STRING
) AS
WITH event_latency_descriptions(
name,
description)
AS (
VALUES
('TouchRendererHandlingToBrowserMain',
'Interval between when the website handled blocking touch move to when ' ||
'the browser UI thread started processing the input. Blocking touch ' ||
'move happens when a touch event has to be handled by the website ' ||
'before being converted to a scroll.'),
('GenerationToBrowserMain',
'Interval between OS-provided hardware input timestamp to when the ' ||
'browser UI thread began processing the input.'),
('GenerationToRendererCompositor',
'Interval between OS-provided hardware input timestamp to when the ' ||
'renderer compositor thread starts handling the artificial TOUCH_PRESS ' ||
'browser injects in the kTouchScrollStarted event. See ' ||
'PrependTouchScrollNotification for more info.'),
('BrowserMainToRendererCompositor',
'Interval between when Browser UI thread starts to process the input to ' ||
'renderer compositor thread starting to process it. This stage includes ' ||
'browser UI thread processing, and task queueing times on the IO and ' ||
'renderer compositor threads.'),
('RendererCompositorQueueingDelay',
'Interval between when the input event is queued in the renderer ' ||
'compositor and start of the BeginImplFrame producing a frame ' ||
'containing this input.'),
('RendererCompositorToMain',
'Interval between when the Renderer Compositor finishes processing the ' ||
'event and when the Renderer Main (CrRendererMain) starts processing ' ||
'the event, only seen when the compositor thread cannot handle the ' ||
'scroll event by itself (known as "slow path"), usually caused by the ' ||
'presence of blocking JS event listeners or complex page layout.'),
('RendererCompositorProcessing',
'Interval corresponding to the Renderer Compositor thread processing ' ||
'the frame updates.'),
('RendererMainProcessing',
'Interval corresponding to the Renderer Main thread processing the ' ||
'frame updates.'),
('EndActivateToSubmitCompositorFrame',
'Interval that the Renderer Compositor waits for the GPU to flush a ' ||
'frame to submit a new one.'),
('SubmitCompositorFrameToPresentationCompositorFrame',
'Interval between the first Renderer Frame received to when the system ' ||
'presented the fully composited frame on the screen. Note that on some ' ||
'systems/apps this is incomplete/inaccurate due to lack of feedback ' ||
'timestamps from the platform (Mac, iOS, Android Webview, etc).'),
('ArrivedInRendererCompositorToTermination',
'Interval between when Renderer Compositor received the frame to when ' ||
'this input was decided to either be ignored or merged into another ' ||
'frame being produced. This could be a dropped frame, or just a normal ' ||
'coalescing.'),
('RendererCompositorStartedToTermination',
'Interval between when Renderer Compositor started processing the frame ' ||
'to when this input was decided to either be ignored or merged into ' ||
'another frame being produced. This could be a dropped frame, or just a ' ||
'normal coalescing.'),
('RendererMainFinishedToTermination',
'Interval between when Renderer Main finished processing the frame ' ||
'to when this input was decided to either be ignored or merged into ' ||
'another frame being produced. This could be a dropped frame, or just a ' ||
'normal coalescing.'),
('RendererCompositorFinishedToTermination',
'Interval between when Renderer Compositor finished processing the ' ||
'frame to when this input was decided to either be ignored or merged ' ||
'into another frame being produced. This could be just a normal ' ||
'coalescing.'),
('RendererMainStartedToTermination',
'Interval between when Renderer Main started processing the frame ' ||
'to when this input was decided to either be ignored or merged into ' ||
'another frame being produced. This could be a dropped frame, or just a ' ||
'normal coalescing.'),
('RendererCompositorFinishedToBeginImplFrame',
'Interval when Renderer Compositor has finished processing a vsync ' ||
'(with input), but did not end up producing a CompositorFrame due to ' ||
'reasons such as waiting on main thread, and is now waiting for the ' ||
'next BeginFrame from the GPU VizCompositor.'),
('RendererCompositorFinishedToCommit',
'Interval between when the Renderer Compositor has finished its work ' ||
'and the current tree state will be committed from the Renderer Main ' ||
'(CrRendererMain) thread.'),
('RendererCompositorFinishedToEndCommit',
'Interval between when the Renderer Compositor finishing processing to ' ||
'the Renderer Main (CrRendererMain) both starting and finishing the ' ||
'commit.'),
('RendererCompositorFinishedToActivation',
'Interval of activation without a previous commit (not as a stage with ' ||
'ToEndCommit). Activation occurs on the Renderer Compositor Thread ' ||
'after it has been notified of a fully committed RendererMain tree.'),
('RendererCompositorFinishedToEndActivate',
'Interval when the Renderer Compositor has finished processing and ' ||
'activating the Tree.'),
('RendererCompositorFinishedToSubmitCompositorFrame',
'Interval when processing does not need to wait for a commit (can do an ' ||
'early out) for activation and can go straight to providing the frame ' ||
'to the GPU VizCompositor. The Renderer Compositor is waiting for the ' ||
'GPU to flush a frame so that it can then submit a new frame.'),
('RendererMainFinishedToBeginImplFrame',
'Interval when the input was sent first to the RendererMain thread and ' ||
'now requires the Renderer Compositor to react, aka it is is waiting ' ||
'for a BeginFrame signal.'),
('RendererMainFinishedToSendBeginMainFrame',
'Interval during which the Renderer Main (CrRendererMain) thread is ' ||
'waiting for BeginMainFrame.'),
('RendererMainFinishedToCommit',
'Interval when the Renderer Main (CrRendererMain) is ready to commit ' ||
'its work to the Renderer Compositor.'),
('BeginImplFrameToSendBeginMainFrame',
'Interval during which the Renderer Compositor has received the ' ||
'BeginFrame signal from the GPU VizCompositor, and now needs to send it ' ||
'to the Renderer Main thread (CrRendererMain).'),
('RendererCompositorFinishedToSendBeginMainFrame',
'Interval during which the Renderer Compositor is waiting for a ' ||
'BeginFrame from the GPU VizCompositor, and it expects to have to do ' ||
'work on the Renderer Main thread (CrRendererMain), so we are waiting ' ||
'for a BeginMainFrame'),
('SendBeginMainFrameToCommit',
'Interval when updates (such as HandleInputEvents, Animate, StyleUpdate ' ||
'and LayoutUpdate) are updatedon the Renderer Main thread ' ||
'(CrRendererMain).'),
('Commit',
'Interval during which the Renderer Main thread (CrRendererMain) ' ||
'commits updates back to Renderer Compositor for activation. ' ||
'Specifically, the main thread copies its own version of layer tree ' ||
'onto the pending tree on the compositor thread. The main thread is ' ||
'blocked during the copying process.'),
('EndCommitToActivation',
'Interval when the commit is ready and waiting for activation.'),
('Activation',
'Interval when the layer trees and properties are on the pending tree ' ||
'is pused to the active tree on the Renderer Compositor.'),
('SubmitToReceiveCompositorFrame',
'Interval of the delay b/w Renderer Compositor thread sending ' ||
'CompositorFrame and then GPU VizCompositorThread receiving the ' ||
'CompositorFrame.'),
('ReceiveCompositorFrameToStartDraw',
'Interval between the first frame received to when all frames (or ' ||
'timeouts have occurred) and we start drawing. It can be blocked by ' ||
'other processes (e.g to draw a toolbar it waiting for information from ' ||
'the Browser) as it waits for timeouts or frames to be provided. This ' ||
'is the tree of dependencies that the GPU VizCompositor is waiting for ' ||
'things to arrive. That is creating a single frame for multiple ' ||
'compositor frames. '),
('StartDrawToSwapStart',
'Interval when all compositing sources are done, or compositing ' ||
'deadline passes - the viz thread takes all the latest composited ' ||
'surfaces and issues the software draw instructions to layer the ' ||
'composited tiles, this substage ends when the swap starts on Gpu ' ||
'CompositorGpuThread.'),
('SwapStartToBufferAvailable',
'Interval that is a substage of stage "Swap" when the framebuffer ' ||
'is prepared by the system and the fence Chrome waits on before ' ||
'writing is signalled, and Chrome can start transferring the new frame.'),
('BufferAvailableToBufferReady',
'Interval that is a Ssubstage of stage "Swap" when Chrome is ' ||
'transferring a new frame to when it has finished completely sending a ' ||
'frame to the framebuffer.'),
('BufferReadyToLatch',
'Interval that is a substage of stage "Swap", when the system latches ' ||
'and is ready to use the frame, and then it can get to work producing ' ||
'the final frame.'),
('LatchToSwapEnd',
'Intereval that is a substage of stage "Swap", when the latch has ' ||
'finished until the frame is fully swapped and in the queue of frames ' ||
'to be presented.'),
('SwapEndToPresentationCompositorFrame',
'Interval that the frame is presented on the screen (and pixels became ' ||
'visible).'))
SELECT
name,
description
FROM event_latency_descriptions;
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