Crate fast_time 

Provides efficient mechanisms to capture the current timestamp and measure elapsed time.

This crate offers a Clock that can provide timestamps with low overhead, making it suitable for high-frequency querying scenarios like metrics collection and logging. The clock prioritizes efficiency over absolute precision, making it ideal for applications that need to capture thousands of timestamps per second.

Key Features

• Low overhead: Optimized for rapid, repeated timestamp capture
• Monotonic timestamps: Guarantees that timestamps always increase
• Cross-platform: Works on both Windows and Linux
• Standard library compatibility: Converts to/from std::time::Instant

Trade-offs

• May lag behind wall-clock time by a few milliseconds
• May not reflect explicit wall clock adjustments (e.g., NTP synchronization)
• Optimized for frequency over precision

Hot loop performance comparison

Platform	fast_time	std::time
Windows	2 ns	25 ns
Linux	6 ns	19 ns

Basic Usage

use fast_time::Clock;

let mut clock = Clock::new();
let start = clock.now();

// Do some work...
std::thread::sleep(std::time::Duration::from_millis(10));

let elapsed = start.elapsed(&mut clock);
println!("Operation took: {:?}", elapsed);

High-frequency timestamp collection

use std::time::Duration;

use fast_time::Clock;

let mut clock = Clock::new();
let mut timestamps = Vec::new();

// Collect many timestamps rapidly
for _ in 0..1000 {
    timestamps.push(clock.now());
}

// Measure elapsed time between first and last
let total_time = timestamps
    .last()
    .unwrap()
    .saturating_duration_since(*timestamps.first().unwrap());

println!(
    "Collected {} timestamps in {:?}",
    timestamps.len(),
    total_time
);

Supported platforms

This crate is tested on:

• Windows 11
• Ubuntu 24

Structs

Clock

A clock that can efficiently provide the current time.

Instant

An instant returned by the fast-time clock.