Measure how much time your function is taking in Rust

One of the ways to benchmark your code in Rust

To optimize our code, we need to measure the performance of our code. One of the ways to measure performance of the code(Compute intensive) is to measure the time taken by the code to execute.

Here is one of the simplest ways to measure the time it takes to execute your function in Rust.

1. Create a new project using cargo new command.

   cargo new benchmarksimple

2. Edit the main.rs file inside the src folder.

use std::time::Instant;
fn main() {
    let now = Instant::now();
    sum_large();
    let elapsed = now.elapsed();
    println!("Elapsed: {:.2?}", elapsed);
}

fn sum_large() -> u64 {
    let mut sum: u64 = 0;
    for i in 1..10000001 {
        sum += i;
    }
    sum
}

3. Execute your code using cargo run command.

   PS C:\crown\benchmarksimple> cargo run
      Compiling benchmarksimple v0.1.0 (C:\crown\benchmarksimple)
       Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.52s
        Running `target\debug\benchmarksimple.exe`
   Elapsed: 53.25ms
   
   PS C:\crown\benchmarksimple> cargo run
       Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.01s
        Running `target\debug\benchmarksimple.exe`
   Elapsed: 56.74ms

There are crates like criterion which can be used with many more functionalities. We will review them in future posts.

Thanks for reading!