Function record_total_and_average

xtask/src/main.rs:5052–5064

(
    total_name: &'static str,
    average_name: &'static str,
    elapsed: Duration,
    iterations: usize,
)

}

fn record_total_and_average(
    total_name: &'static str,
    average_name: &'static str,
    elapsed: Duration,
    iterations: usize,
) {
    record_phase_timing(total_name, elapsed);
    let average = elapsed.as_micros() / iterations as u128;
    record_phase_timing(
        average_name,
        Duration::from_micros(average.try_into().unwrap_or(u64::MAX)),
    );
}

fn unique_perf_root(name: &str) -> Result<PathBuf> {
    let now = SystemTime::now()