Struct PhaseTimer 

pub struct PhaseTimer { /* private fields */ }

Lightweight sub-phase timer for hot-path instrumentation.

Zero overhead when disabled (all methods are no-ops). When enabled, captures phase boundaries via mark() and emits structured timing via emit().

Implementations

impl PhaseTimer

pub fn from_env(env_var: &'static str, label: &'static str) -> Self

Create a timer controlled by an environment variable.

Returns a disabled (zero-cost) timer if the env var is unset or != “1”.

pub fn start(&mut self)

Start a new timing cycle. Call at the top of each iteration.

pub fn mark(&mut self, phase: &'static str)

Mark the end of a named phase. The duration is from the previous mark (or start) to now.

pub fn emit(&self, iteration: u64, batch_size: usize)

Emit timing data if enabled and the iteration matches the emit interval.

Default interval: first 5 iterations, then every 100.

pub fn is_enabled(&self) -> bool

Check if the timer is enabled.