diff options
| -rw-r--r-- | 2018/src/benchmark.rs | 45 |
1 files changed, 30 insertions, 15 deletions
diff --git a/2018/src/benchmark.rs b/2018/src/benchmark.rs index 76de9e4..697fa8e 100644 --- a/2018/src/benchmark.rs +++ b/2018/src/benchmark.rs @@ -7,13 +7,13 @@ const MIN_TIMES: usize = 4; pub struct Bench { pub executions: usize, pub duration: f64, - pub duration_stddev: f64, + pub duration_stderr: f64, } impl fmt::Display for Bench { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f, "{} secs ± {} ({}%)", - self.duration, self.duration_stddev, self.duration_stddev / self.duration * 100.0) + self.duration, self.duration_stderr, self.duration_stderr / self.duration * 100.0) } } @@ -51,28 +51,43 @@ pub fn benchmark<A, F: Fn() -> A>(func: F) -> Bench { let nparts = if ntimes_guess < 10 { ntimes_guess } else { - std::cmp::max(10, ntimes_guess / 10) + std::cmp::max(10, ntimes_guess / 100) }; let nperpart = (ntimes_guess + nparts - 1) / nparts; - let ntimes = nparts * nperpart; - // eprintln!("BENCH: estimate={} ntimes_guess={} nparts={} nperpart={} ntimes={}", estimate, ntimes_guess, nparts, nperpart, ntimes); - let mut times = vec![0.0; nparts]; + let mut times = Vec::new(); - for i in 0..nparts { - let start = Instant::now(); - for _ in 0..nperpart { - func(); + let mut mean = 0.0; + let mut stderr = 0.0; + + eprint!("BENCH: Running {} blocks of {} calls...", nparts, nperpart); + + for _ in 0..6 { + for _ in 0..nparts { + let start = Instant::now(); + for _ in 0..nperpart { + func(); + } + let end = Instant::now(); + + times.push(duration_secs(end - start)); + } + + let partmean = times.iter().map(|&t| t).sum::<f64>() / times.len() as f64; + let stddev = (times.iter().map(|&t| (t - partmean) * (t - partmean)).sum::<f64>() / (times.len() - 1) as f64).sqrt(); + stderr = stddev / (times.len() as f64).sqrt(); + mean = partmean / nperpart as f64; + + if stderr / mean < 0.05 { + break; } - let end = Instant::now(); - times[i] = duration_secs(end - start); + eprint!(" again({},{})", mean, stderr); } - let mean = times.iter().map(|&t| t).sum::<f64>() / ntimes as f64; - let stddev = times.iter().map(|t| (t - mean) * (t - mean)).sum::<f64>() / (ntimes - 1) as f64; + eprintln!(""); - Bench { executions: 0, duration: mean, duration_stddev: stddev } + Bench { executions: times.len() * nperpart, duration: mean, duration_stderr: stderr } } |