Enum Tracer 

pub enum Tracer {
    Active(Arc<ActiveTracer>),
    Noop,
}

Performance tracer that emits Chrome Trace Event Format data.

Variants

Active(Arc<ActiveTracer>)

Actively collecting trace events.

Noop

No-op tracer that discards all events.

Implementations

impl Tracer

pub fn new() -> Self

Creates a new active tracer with the current instant as epoch.

pub fn noop() -> Self

Creates a no-op tracer that discards all events.

pub fn complete_event( &self, name: &str, cat: &str, pid: u32, tid: u32, start_us: f64, dur_us: f64, args: Option<Value>, )

Records a complete (“X”) event with explicit start time and duration.

pub fn instant_event( &self, name: &str, cat: &str, pid: u32, tid: u32, args: Option<Value>, )

Records an instant (“i”) event with thread scope.

pub fn metadata_event(&self, name: &str, pid: u32, tid: u32, args: Value)

Records a metadata (“M”) event (e.g. for process_name, thread_name).

pub fn span(&self, name: &str, cat: &str, pid: u32, tid: u32) -> SpanGuard

Creates an RAII span guard that records a complete event on drop.

pub fn elapsed_us(&self) -> f64

Returns microseconds elapsed since the tracer epoch (0.0 for Noop).

pub fn to_json(&self) -> Result<String, Error>

Serializes all collected events to a JSON array string.

pub fn write_to_file(&self, path: &Path) -> Result<()>

Writes the JSON trace to a file (no-op for Noop).

Trait Implementations

impl Clone for Tracer

fn clone(&self) -> Tracer

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Default for Tracer

fn default() -> Self

Returns the “default value” for a type.