Struct StartupSpans 

pub struct StartupSpans<C: Clock = SystemClock> { /* private fields */ }

Named monotonic timestamps from a begin() epoch — a shell records one named span at each startup milestone (see the SPAN_* consts), then calls Self::emit_log once for a single summary line.

Implementations

impl StartupSpans<SystemClock>

pub fn begin() -> Self

Begin a span recorder honoring the process-wide enabled switch, using the real system clock — what every shell constructs.

impl<C: Clock> StartupSpans<C>

pub fn begin_with_enabled(clock: C, is_enabled: bool) -> Self

Test/advanced seam: begin with an explicit clock and enabled flag, bypassing enabled’s cache (see FrameStats::new_enabled’s docs for why).

pub fn record(&mut self, name: &'static str)

Record name at the current clock reading, as a delta from Self::begin’s epoch. A no-op (no clock read, no allocation) when disabled.

pub fn record_duration(&mut self, name: &'static str, duration: Duration)

Record name with an explicit duration, for a span measured elsewhere (the first frame’s submit sub-spans, timed inside frust-render, which cannot see this recorder).

Unlike Self::record the value is NOT an offset from the epoch: the line prints it as-is, so first_submit_* fields read as milliseconds spent, and the three sum to about the first frame’s submit span. They are inserted between first_encode_done and first_frame_presented. A no-op when disabled.

pub fn offset_of(&self, name: &str) -> Option<Duration>

The recorded offset of the first span called name, if any.

pub fn record_install_steps( &mut self, steps: &InstallSteps, start_ref: Option<&str>, )

Record every install sub-step as a duration. With start_ref, also record SPAN_RENDER_THREAD_START_MS: the start_ref to adapter_ready gap less the install’s own total (call after adapter_ready is recorded; skipped when either span is missing).

pub fn record_font_steps(&mut self, font_system: Duration, app_sync: Duration)

Record the two TextContext::new halves as durations.

pub fn spans(&self) -> &[(&'static str, Duration)]

The recorded (name, delta) pairs in insertion order.

pub fn emit_log(&self)

Emit one frust-perf startup ... line via log::info! containing every recorded span’s name and millisecond delta, in insertion order. A no-op when disabled or when nothing has been recorded.