psi 0.1.2

Linux Pressure Stall Information (PSI) for Rust
Documentation 
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extern crate log;
extern crate psi;
extern crate simplelog;

use std::fs::OpenOptions;
use std::io::Write;
use std::time::Duration;

use log::*;
use simplelog::*;

use psi::error::*;
use psi::*;

const SYSRQ_TRIGGER_PATH: &'static str = "/proc/sysrq-trigger";

pub fn low_mem_handler() -> Result<()> {
    Ok(())
}

pub fn trigger_oom_killer() -> Result<()> {
    warn!("triggering oom killer");
    let mut sysrq = OpenOptions::new().write(true).open(SYSRQ_TRIGGER_PATH)?;
    Ok(sysrq.write_all(&['f' as u8])?)
}

fn main() -> Result<()> {
    SimpleLogger::init(LevelFilter::Trace, Config::default())?;
    let mut monitor = PsiMonitor::new()?;
    let low_mem_id = monitor.add_trigger(
        Trigger::new_builder()
            .memory()
            .full()
            .stall(Duration::from_millis(50))
            .window(Duration::from_millis(500))
            .build(),
    )?;
    let oom_id = monitor.add_trigger(
        Trigger::new_builder()
            .memory()
            .full()
            .stall(Duration::from_millis(100))
            .window(Duration::from_millis(500))
            .build(),
    )?;
    loop {
        let psi_event = monitor.wait_single()?;
        debug!("{:?}", psi_event.stats);
        if oom_id == psi_event.id {
            info!("out of memory threshold reached");
            trigger_oom_killer()?;
        } else if low_mem_id == psi_event.id {
            info!("low memory threshold reached");
            low_mem_handler()?;
        }
    }
}