trace_time/
lib.rs

1// Copyright 2020 Parity Technologies
2//
3// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
4// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
5// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
6// option. This file may not be copied, modified, or distributed
7// except according to those terms.
8
9//! Performance timer with logging
10
11use log::trace;
12use std::time::Instant;
13
14#[macro_export]
15macro_rules! trace_time {
16	($name: expr) => {
17		let _timer = $crate::PerfTimer::new($name);
18	};
19}
20
21/// Performance timer with logging. Starts measuring time in the constructor, prints
22/// elapsed time in the destructor or when `stop` is called.
23pub struct PerfTimer {
24	name: &'static str,
25	start: Instant,
26}
27
28impl PerfTimer {
29	/// Create an instance with given name.
30	pub fn new(name: &'static str) -> PerfTimer {
31		PerfTimer { name, start: Instant::now() }
32	}
33}
34
35impl Drop for PerfTimer {
36	fn drop(&mut self) {
37		let elapsed = self.start.elapsed();
38		let ms = elapsed.as_millis();
39		trace!(target: "perf", "{}: {:.2}ms", self.name, ms);
40	}
41}
trace_time/lib.rs

trace_time/
lib.rs
