slowrendering

Slow Rendering Instrumentation

Status: development

The OpenTelemetry slow rendering instrumentation for Android will detect when the application user interface is slow or frozen. See the Android documentation for a discussion of UI "jank".

The instrumentation operates by periodically polling for frame metrics, by default every 1 second.

Telemetry

This instrumentation produces the following telemetry, with an instrumentation scope of app.jank.

Slow Renders (Event)

Generated when rendering takes more than 16ms within a polling period.

• Type: Event
• Event Name: app.jank
• Description: This event is emitted when frame metrics contain at least one render duration longer than 16ms (the slow rendering threshold).
• Attributes:
  • app.jank.frame_count - the number of frames that exceeded the threshold
  • app.jank.period - the polling period duration in seconds during which the frames were detected
  • app.jank.threshold - the threshold in seconds above which a frame is considered slow (e.g. 0.016)

Frozen Renders (Event)

Generated when rendering takes more than 700ms within a polling period.

• Type: Event
• Event Name: app.jank
• Description: This event is emitted when frame metrics contain at least one render duration longer than 700ms (the frozen rendering threshold).
• Attributes:
  • app.jank.frame_count - the number of frames that exceeded the threshold
  • app.jank.period - the polling period duration in seconds during which the frames were detected
  • app.jank.threshold - the threshold in seconds above which a frame is considered frozen (e.g. 0.7)

Deprecated: Zero-Duration Spans

Deprecated. Zero-duration spans are no longer emitted by default. They can be re-enabled via enableDeprecatedZeroDurationSpan() for backwards compatibility, but this is discouraged. Use the app.jank events above instead.

When enabled via enableDeprecatedZeroDurationSpan(), the instrumentation additionally produces spans with an instrumentation scope of io.opentelemetry.slow-rendering.

Slow Renders (Span)

• Type: Span (zero duration)
• Name: slowRenders
• Attributes:
  • count - the number of slow renders
  • activity.name - the name of the activity for which the slow render was detected

Frozen Renders (Span)

• Type: Span (zero duration)
• Name: frozenRenders
• Attributes:
  • count - the number of frozen renders
  • activity.name - the name of the activity for which the frozen render was detected

Installation

This instrumentation comes with the android agent out of the box, so if you depend on it, you don't need to do anything else to install this instrumentation. However, if you don't use the agent but instead depend on core directly, you can manually install this instrumentation by following the steps below.

Adding dependencies

implementation("io.opentelemetry.android.instrumentation:slowrendering:1.2.0-alpha")