Module analysis 

What a timeline says, read the same way by every reader (ADR 0058, decisions 9 and 10): a frame’s phases, the path from an input to the screen, a verdict on why it lagged, the runs of frames with no input, and the recording grouped by span, by origin and by what its gaps held.

Structs

Burn

A run of frames with no input: indices into the timeline’s frames.

Gaps

What the gaps between frames held, summed over the timeline, µs.

InputPath

The path from the first input frame i answers to the driver’s present record, in timeline µs. This does not measure physical display.

Phases

A frame’s time by phase, µs.

PlacementStat

A component kind’s placements over the timeline: how many, how many replayed, and the rest by answer and reason, the most first.

SpanStat

A span name’s spread over frames: calls, total, self, worst, and CPU where read.

Enums

Verdict

Why a frame lagged, the first that holds (ADR 0058, decision 9).

Constants

BUILD

The core’s own spans (origin Origin::Kui) and the drivers’.

BURN_FRAMES

A burn: at least this many frames…

BURN_GAP_US

…each within this of the one before (µs), with no input among them.

DEVTOOLS

EMIT

FILL

An extension’s fill is fill <namespace>.

HANDLER

A driver’s call into the app’s event handler (origin Origin::Host).

INPUT_CAUSES

The frame-cause kinds that are input: a run of frames with none of them is a burn.

LAYOUT

REPLAYED

A placement’s answer when its last fill was pushed again.

Traits

NameOf

Something that turns a name id into its string: a crate::Trace or a writer’s crate::Names.

Functions

burns

Every burn: BURN_FRAMES frames or more, each beginning within BURN_GAP_US of the one before, none answering input.

by_origin

Self time by origin — the host, each extension, kui — the most first.

by_span

Every span of the timeline, grouped by name and origin, the most total first.

counters

Each counter’s average a frame and its most, by name. A frame that recorded no value for a counter counts as 0 — the core writes a counter only where it moved — so a glyph rasterized once in a hundred frames averages 0.01, not 1.

gaps

gaps_in

Gaps preceding selected original frame indices. A sliced population keeps the original preceding gap, rather than treating its first frame as frame 0.

gauges

Each gauge’s last, least and most, by name.

input_path

Frame i’s input path, when an input arrived in its gap.

phases

Frame i’s phases: the core’s spans inside it, the handlers in its gap, the driver’s present.

placements

Every placement of the timeline, grouped by component kind, the most drawn fresh first.

spread

(avg, p95, max) of v; zeros for none.

verdict

Frame i’s verdict against budget µs; burns from burns.