scx_cosmos/
stats.rs

1use std::io::Write;
2use std::sync::atomic::AtomicBool;
3use std::sync::atomic::Ordering;
4use std::sync::Arc;
5use std::time::Duration;
6
7use anyhow::Result;
8use scx_stats::prelude::*;
9use scx_stats_derive::stat_doc;
10use scx_stats_derive::Stats;
11use serde::Deserialize;
12use serde::Serialize;
13
14#[stat_doc]
15#[derive(Clone, Debug, Default, Serialize, Deserialize, Stats)]
16#[stat(top)]
17pub struct Metrics {
18    #[stat(desc = "Average CPU utilization %")]
19    pub cpu_util: u64,
20    #[stat(desc = "Busy utilization threshold %")]
21    pub cpu_thresh: u64,
22    #[stat(desc = "Direct dispatch due to high perf events (migration)")]
23    pub nr_event_dispatches: u64,
24    #[stat(desc = "Kept on same CPU due to perf sticky threshold")]
25    pub nr_ev_sticky_dispatches: u64,
26}
27
28impl Metrics {
29    fn format<W: Write>(&self, w: &mut W) -> Result<()> {
30        writeln!(
31            w,
32            "[{}] CPUs {:>5.1}% {} ev_dispatches={} ev_sticky_dispatches={}",
33            crate::SCHEDULER_NAME,
34            (self.cpu_util as f64) * 100.0 / 1024.0,
35            if self.cpu_util >= self.cpu_thresh {
36                "[deadline]"
37            } else {
38                "[round-robin]"
39            },
40            self.nr_event_dispatches,
41            self.nr_ev_sticky_dispatches,
42        )?;
43        Ok(())
44    }
45
46    fn delta(&self, rhs: &Self) -> Self {
47        Self {
48            nr_event_dispatches: self.nr_event_dispatches - rhs.nr_event_dispatches,
49            nr_ev_sticky_dispatches: self.nr_ev_sticky_dispatches - rhs.nr_ev_sticky_dispatches,
50            ..self.clone()
51        }
52    }
53}
54
55pub fn server_data() -> StatsServerData<(), Metrics> {
56    let open: Box<dyn StatsOpener<(), Metrics>> = Box::new(move |(req_ch, res_ch)| {
57        req_ch.send(())?;
58        let mut prev = res_ch.recv()?;
59
60        let read: Box<dyn StatsReader<(), Metrics>> = Box::new(move |_args, (req_ch, res_ch)| {
61            req_ch.send(())?;
62            let cur = res_ch.recv()?;
63            let delta = cur.delta(&prev);
64            prev = cur;
65            delta.to_json()
66        });
67
68        Ok(read)
69    });
70
71    StatsServerData::new()
72        .add_meta(Metrics::meta())
73        .add_ops("top", StatsOps { open, close: None })
74}
75
76pub fn monitor(intv: Duration, shutdown: Arc<AtomicBool>) -> Result<()> {
77    scx_utils::monitor_stats::<Metrics>(
78        &[],
79        intv,
80        || shutdown.load(Ordering::Relaxed),
81        |metrics| metrics.format(&mut std::io::stdout()),
82    )
83}
scx_cosmos/stats.rs

scx_cosmos/
stats.rs
