runnerd_core/api/
units.rs

1//! How every client writes times and CPU use: durations, ages, CPU time, and cores in use. One rounding policy each,
2//! so the dashboard, the TUI, `runnerctl` and the daemon's own commands print the same figure for the same value.
3//! A limit (a cap, a reservation) is in CPUs to a tenth rounded up, by [`cpus`](super::cpus); use is in cores to a
4//! hundredth rounded up, here. Pure functions of their arguments; the caller passes the current time.
5
6/// Seconds as a stopwatch writes them, its width holding as it counts: `45s`, `1m 12s`, `2h 05m`, `3d 4h`.
7pub fn duration(seconds: u64) -> String {
8    match seconds {
9        0..60 => format!("{seconds}s"),
10        60..3600 => format!("{}m {:02}s", seconds / 60, seconds % 60),
11        3600..86_400 => format!("{}h {:02}m", seconds / 3600, seconds % 3600 / 60),
12        _ => format!("{}d {}h", seconds / 86_400, seconds % 86_400 / 3600),
13    }
14}
15
16/// How long ago `at` was: `just now` under ten seconds, then as [`duration`] writes it, `1h 05m ago`.
17pub fn ago(at: u64, now: u64) -> String {
18    match now.saturating_sub(at) {
19        0..10 => "just now".to_owned(),
20        seconds => format!("{} ago", duration(seconds)),
21    }
22}
23
24/// CPU time given in milliseconds: `4.6s` to a tenth under a minute, then as [`duration`] writes it.
25pub fn cpu_time(milliseconds: u64) -> String {
26    if milliseconds < 60_000 {
27        let tenths = (milliseconds + 50) / 100;
28        format!("{}.{}s", tenths / 10, tenths % 10)
29    } else {
30        duration(milliseconds / 1000)
31    }
32}
33
34/// Millicores in use as cores, to a hundredth rounded up so use never reads as none: `0.25`, `1.5`, `12`, `0.01`.
35pub fn cores_used(millicores: u64) -> String {
36    let hundredths = millicores.div_ceil(10);
37    let (whole, part) = (hundredths / 100, hundredths % 100);
38    if part == 0 {
39        whole.to_string()
40    } else if part.is_multiple_of(10) {
41        format!("{whole}.{}", part / 10)
42    } else {
43        format!("{whole}.{part:02}")
44    }
45}
46
47/// Millicores in use as [`cores_used`] writes them, with the unit: `1.5 cores`, `1 core`.
48pub fn in_cores(millicores: u64) -> String {
49    match cores_used(millicores).as_str() {
50        "1" => "1 core".to_owned(),
51        number => format!("{number} cores"),
52    }
53}
54
55#[cfg(test)]
56mod tests {
57    use super::*;
58
59    #[test]
60    fn a_duration_reads_like_a_stopwatch_in_every_client() {
61        assert_eq!(duration(9), "9s");
62        assert_eq!(duration(72), "1m 12s");
63        assert_eq!(duration(3909), "1h 05m");
64        assert_eq!(duration(3 * 86_400 + 4 * 3600), "3d 4h");
65    }
66
67    #[test]
68    fn an_age_is_the_duration_since() {
69        assert_eq!(ago(100, 105), "just now");
70        assert_eq!(ago(0, 3909), "1h 05m ago");
71        assert_eq!(
72            ago(200, 100),
73            "just now",
74            "a time ahead of the clock is now"
75        );
76    }
77
78    #[test]
79    fn cpu_time_keeps_work_under_a_second() {
80        assert_eq!(cpu_time(4600), "4.6s");
81        assert_eq!(cpu_time(600), "0.6s");
82        assert_eq!(cpu_time(125_000), "2m 05s");
83    }
84
85    #[test]
86    fn cores_in_use_never_read_as_none() {
87        assert_eq!(cores_used(1), "0.01");
88        assert_eq!(cores_used(250), "0.25");
89        assert_eq!(cores_used(1500), "1.5");
90        assert_eq!(cores_used(12_000), "12");
91        assert_eq!(cores_used(0), "0");
92        assert_eq!(in_cores(1000), "1 core");
93        assert_eq!(in_cores(1250), "1.25 cores");
94    }
95}
runnerd_core/api/units.rs

runnerd_core/api/
units.rs
