gistfile1.txt

use std::time::Instant;
use std::time::Duration;

fn meas(n: usize, f: fn(n: usize, iters: usize, inpv: Vec<Vec<u8>>, outpv: &mut Vec<Vec<u8>>, measures: &mut Vec<Duration>)->(), setup_for_f: fn(n: usize, iters: usize, inpv: &mut Vec<Vec<u8>>, outpv: &mut Vec<Vec<u8>>)->()) {
  let iters : usize = 800;
  let mut inpv : Vec<Vec<u8>> = Vec::with_capacity(iters);
  let mut outpv : Vec<Vec<u8>> = Vec::with_capacity(iters);
  let mut measures : Vec<Duration> = Vec::with_capacity(iters);

  setup_for_f(n, iters, &mut inpv, &mut outpv);
  let prev = Instant::now();
  f(n, iters, inpv, &mut outpv, &mut measures);
  let dur = Instant::now() - prev;

  let mean = dur.checked_div(iters as u32).unwrap();

  measures.sort();
  let mut sum : u128 = 0;
  for measure in &measures {
    sum += measure.as_nanos()
  };
  let len = measures.len();
  let min = measures[0];
  let max = measures[len-1];
  let med = measures[len/2];
  println!("n: {:05?}, tot mean: {:?}, sum mean: {:?}, min: {:?}, max: {:?}, median: {:?}", n, mean, Duration::from_nanos((sum/(iters as u128)) as u64), min, max, med);
}

fn setup_for_nop(_n: usize, _iters: usize, _inpv: &mut Vec<Vec<u8>>, _outpv: &mut Vec<Vec<u8>>) {}

fn nop(_n: usize, iters: usize, _inpv: Vec<Vec<u8>>, _outpv: &mut Vec<Vec<u8>>, measures: &mut Vec<Duration>) {
  let mut x = 0;
  let mut prev = Instant::now();
  for _i in 0..iters {
     x = x + 3;
     let now = Instant::now();
     measures.push(now-prev);
     prev = now;
  }
}

fn setup_for_alloc(_n: usize, _iters: usize, _inpv: &mut Vec<Vec<u8>>, _outpv: &mut Vec<Vec<u8>>) {}

fn alloc(n: usize, iters: usize, _inpv: Vec<Vec<u8>>, outpv: &mut Vec<Vec<u8>>, measures: &mut Vec<Duration>) {
  let mut prev = Instant::now();
  for _i in 0..iters {
    let v : Vec<u8> = Vec::with_capacity(n);
    outpv.push(v);
    let now = Instant::now();
    measures.push(now-prev);
    prev = now;
  }
}

fn setup_for_copy(n: usize, iters: usize, inpv: &mut Vec<Vec<u8>>, outpv: &mut Vec<Vec<u8>>) {
    for _i in 0..iters {
        let mut iv : Vec<u8> = Vec::with_capacity(n);
        iv.resize(n, 1);
        inpv.push(iv);

        let ov : Vec<u8> = Vec::with_capacity(n);
        outpv.push(ov);
    }
}

fn copy(_n: usize, iters: usize, inpv: Vec<Vec<u8>>, outpv: &mut Vec<Vec<u8>>, measures: &mut Vec<Duration>) {
  let mut prev = Instant::now();
  for i in 0..iters {
    outpv[i].extend_from_slice(&inpv[i]);
    let now = Instant::now();
    measures.push(now-prev);
    prev = now;
  }
}

fn main() {
  println!("Hello, world!");

  println!("nop...");
  let mut i : usize;
  
  const MAXN : usize = 300_000;
  const EXP : f32 = 1.4;
  
  i = 24;
  while i < MAXN {
    meas(i, nop, setup_for_nop);
    i = ((i as f32) * EXP) as usize;    
  }

  println!("alloc...");
  i = 24;
  while i < MAXN {
    meas(i, alloc, setup_for_alloc);
    i = ((i as f32) * EXP) as usize;    
  }
  
  println!("copy...");
  i = 24;
  while i < MAXN {
    meas(i, copy, setup_for_copy);
    i = ((i as f32) * EXP) as usize;    
  }

    println!("Goodbye, world!")
}