<!--
Copyright 2020 The Chromium Authors
Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
-->
<!--
This file is used to generate a comprehensive list of WebAudio histograms
along with a detailed description for each histogram.
For best practices on writing histogram descriptions, see
https://chromium.googlesource.com/chromium/src.git/+/HEAD/tools/metrics/histograms/README.md
Please follow the instructions in the OWNERS file in this directory to find a
reviewer. If no OWNERS file exists, please consider signing up at
go/reviewing-metrics (Googlers only), as all subdirectories are expected to
have an OWNERS file. As a last resort you can send the CL to
[email protected].
-->
<histogram-configuration>
<histograms>
<histogram name="WebAudio.AudioBuffer.Length" units="frames"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The length (in frames) requested by createBuffer(). Recorded for every call
to createBuffer(). Probably many (tens or hundreds) per page.
</summary>
</histogram>
<histogram name="WebAudio.AudioBuffer.NumberOfChannels" units="units"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The number of channels requested by createBuffer(). Recorded for every call
to createBuffer(). Probably many (tens or hundreds) per page.
</summary>
</histogram>
<histogram name="WebAudio.AudioBuffer.SampleRate384kHz" units="Hz"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The sample rate (in Hz) requested by createBuffer(). Recorded for every call
to createBuffer(). Probably many (tens or hundreds) per page.
</summary>
</histogram>
<histogram name="WebAudio.AudioBuffer.SampleRateRatio384kHz" units="units"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The ratio of the buffer sample rate from createBuffer() to the context
sample rate. This indicates if the buffer needs to be resampled. Recorded
for every call to createBuffer(). Probably many (tens or hundreds) per page.
</summary>
</histogram>
<histogram name="WebAudio.AudioContext.CreateTime" units="ms"
expires_after="2025-02-02">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
Measures the time it takes to create the AudioContext object. This is
recorded every time an AudioContext is successfully created.
</summary>
</histogram>
<histogram name="WebAudio.AudioContext.HardwareSampleRate" units="Hz"
expires_after="2025-02-02">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The hardware sample rate (in Hz) used by an AudioContext. Recorded for every
WebAudio AudioContext that is created; probably only one or two per page.
</summary>
</histogram>
<histogram name="WebAudio.AudioContext.latencyHintCategory" units="units"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
If provided, the latencyHint option category of "interactive",
"balanced", "playback", or "exact", in that
order where "exact" means an explicit floating point value was
provided. Recorded for every AudioContext that is constructed with a
latencyHint.
</summary>
</histogram>
<histogram name="WebAudio.AudioContext.latencyHintMilliSeconds" units="ms"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
If the latencyHint is provided and is a floating-point number, the value in
milliseconds is recorded. This is recorded for every AudioContext that is
constructed with a floating-point latencyHint value.
</summary>
</histogram>
<histogram name="WebAudio.AudioContext.MaxChannelsAvailable" units="units"
expires_after="2025-02-02">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The maximum number of (hardware) channels available in an AudioContext.
Recorded for every WebAudio AudioContext that is created; probably only one
or two per page.
</summary>
</histogram>
<histogram name="WebAudio.AudioContext.Operation"
enum="WebAudioContextOperation" expires_after="2025-02-02">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
Tracks occurences of AudioContext operations, to allow assessing what
proportion of AudioContexts are explicitly closed.
</summary>
</histogram>
<histogram name="WebAudio.AudioContextOptions.sampleRate" units="Hz"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The sample rate requested by developer to be used as the sample rate when
constructing an AudioContext with an AudioContextOptions dictionary. This is
recorded for each AudioContext created, probably just one or two per page.
</summary>
</histogram>
<histogram name="WebAudio.AudioContextOptions.sampleRateRatio" units="units"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The ratio of the user-selected sample rate to the hardware sample rate of an
AudioContext. The ratio is represented as a percentage. This is recorded for
each AudioContext created, probably just one or two per page.
</summary>
</histogram>
<histogram name="WebAudio.AudioDestination.CallbackBufferSize" units="units"
expires_after="2025-02-02">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The callback buffer size (in audio frames) for WebAudio rendering between
the WebAudio graph and the audio device thread. This can differ from the
value recommended by the audio hardware due to internal constraints in
WebAudio. Recorded for every WebAudio AudioContext that is created.
</summary>
</histogram>
<histogram name="WebAudio.AudioDestination.HardwareBufferSize" units="units"
expires_after="2025-02-02">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The buffer size (in audio frames) for WebAudio rendering recommended by the
audio hardware. Recorded for every WebAudio AudioContext that is created.
</summary>
</histogram>
<histogram name="WebAudio.AudioDestination.HardwareOutputLatency" units="ms"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The latency reported from the audio hardware. This number can be dynamic at
runtime but the metric is collected only once at the first platform audio
callback after an AudioContext is created.
</summary>
</histogram>
<histogram name="WebAudio.AudioWorklet.PeakDedicatedBackingThreadCount"
units="threads" expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The maximum number of dedicated backing worklet threads throughout the
lifetime of the document/frame.
</summary>
</histogram>
<histogram name="WebAudio.AudioWorklet.PeakSharedBackingThreadRefCount"
units="refcounts" expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The maximum number of ref counts using the shared backing thread throughout
the lifetime of the document/frame.
</summary>
</histogram>
<histogram name="WebAudio.Autoplay" enum="WebAudioAutoplayStatus"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The autoplay status of an AudioContext when destroyed. This include all
types of frames. In order to know the value only for main frames, the
.CrossOrigin values can be substracted.
</summary>
</histogram>
<histogram name="WebAudio.Autoplay.CrossOrigin" enum="WebAudioAutoplayStatus"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The autoplay status of an AudioContext when destroyed in a cross-origin
frame.
</summary>
</histogram>
<histogram name="WebAudio.Autoplay.UnlockType"
enum="WebAudioAutoplayUnlockType" expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
Records how an AudioContext was unlocked (if it was). This is recorded when
the AudioContext is destroyed.
</summary>
</histogram>
<histogram name="WebAudio.BiquadFilter.Type" enum="BiquadFilterType"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The type of the BiquadFilterNode. Recorded each time the type is set. This
recorded once (to lowpass) when a biquad filter is created and also recorded
whenever the filter type changes due to user action or programatically. It
is unlikely the type will change more than once.
</summary>
</histogram>
<histogram name="WebAudio.ConvolverNode.ImpulseResponseLength" units="ms"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The duration in millisec of impulse responses for a ConvolverNode. Recorded
each time the impulse response is set for a ConvolverNode.
</summary>
</histogram>
<histogram name="WebAudio.IIRFilterNode.Order" units="units"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The order of the WebAudio IIRFilterNode. The order is one less than the
number of feedback coefficients used in the denominator of the IIRFilter
transfer function. Recorded each time an IIRFilter is constructed.
</summary>
</histogram>
<histogram name="WebAudio.OfflineAudioContext.CreateTime" units="ms"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
Measures the time it takes to create the OfflineAudioContext object. This is
recorded every time an OfflineAudioContext is successfully created.
</summary>
</histogram>
<histogram name="WebAudio.PannerNode.PanningModel" enum="PanningModelType"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
The panning model for the PannerNode. Recorded once with the default value
at creation and once again whenver it is changed. Once changed, it is
unlikely to be changed again. If there are any PannerNodes created at all,
then there is probably one for each source (AudioBufferSourceNode,
OscillatorNode, or other source).
</summary>
</histogram>
<histogram name="WebAudio.PushPullFIFO.UnderflowGlitches" enum="Boolean"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
Captures if WebAudio caused glitches or not due to the FIFO underflow. It is
recorded when PushPullFIFO is destroyed. (e.g. navigating away from the
page.)
</summary>
</histogram>
<histogram name="WebAudio.PushPullFIFO.UnderflowPercentage" units="%"
expires_after="2024-12-01">
<owner>[email protected]</owner>
<owner>[email protected]</owner>
<owner>src/third_party/blink/renderer/modules/webaudio/OWNERS</owner>
<summary>
Percentage of FIFO underflow happened due to the the missed deadline of
WebAudio rendering engine. It is recorded when PushPullFIFO is destroyed.
(e.g. navigating away from the page.)
</summary>
</histogram>
</histograms>
</histogram-configuration>
Codebase Browser
chromium