Struct Timer 

pub struct Timer { /* private fields */ }

High-level timer for measuring function execution.

Wraps the low-level cycle counter with calibration and conversion to nanoseconds.

Implementations

impl Timer

pub fn new() -> Self

Create a new timer with automatic calibration.

pub fn with_cycles_per_ns(cycles_per_ns: f64) -> Self

Create a timer with a known cycles-per-nanosecond value.

Useful for testing or when calibration has already been done.

pub fn cycles_per_ns(&self) -> f64

Get the calibrated cycles per nanosecond.

pub fn resolution_ns(&self) -> f64

Get the estimated timer resolution in nanoseconds.

On x86_64, this is typically ~0.3-1ns (CPU frequency TSC). On aarch64, this varies by SoC: ~1ns on ARMv8.6+ (Graviton4), ~40ns on Apple Silicon/Ampere Altra, ~18ns on Raspberry Pi 4.

pub fn suggested_iterations(&self, target_resolution_ns: f64) -> usize

Suggest minimum iterations per sample based on timer resolution.

For operations faster than the timer resolution, batching multiple iterations per measurement ensures reliable timing data.

Arguments

• target_resolution_ns - Desired effective resolution (default: 10ns)

Returns

Recommended iterations per sample (minimum 1).

pub fn measure_cycles<F, T>(&self, f: F) -> MeasurementResult

where F: FnOnce() -> T,

Measure the execution time of a function in cycles.

Uses black_box to prevent optimization of the measured function.

Errors

This implementation always succeeds (register-based timers cannot fail), but returns Result for API consistency with PMU-based timers.

pub fn measure_ns<F, T>(&self, f: F) -> Result<f64, MeasurementError>

where F: FnOnce() -> T,

Measure the execution time of a function in nanoseconds.

Errors

This implementation always succeeds (register-based timers cannot fail), but returns Result for API consistency with PMU-based timers.

pub fn cycles_to_ns(&self, cycles: u64) -> f64

Convert cycles to nanoseconds using calibrated ratio.

pub fn measure_batched_cycles<F, T>( &self, iterations: usize, f: F, ) -> MeasurementResult

where F: FnMut() -> T,

Measure batched iterations and return per-iteration cycles.

Runs the function iterations times and returns the average cycles per iteration. This is useful when timer resolution is too coarse for single-iteration measurements.

Errors

This implementation always succeeds (register-based timers cannot fail), but returns Result for API consistency with PMU-based timers.

pub fn measure_batched_ns<F, T>( &self, iterations: usize, f: F, ) -> Result<f64, MeasurementError>

where F: FnMut() -> T,

Measure batched iterations and return per-iteration nanoseconds.

Errors

This implementation always succeeds (register-based timers cannot fail), but returns Result for API consistency with PMU-based timers.

Trait Implementations

impl Clone for Timer

fn clone(&self) -> Timer

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Timer

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Timer

fn default() -> Self

Returns the “default value” for a type.