Enum WakeUpOn

pub enum WakeUpOn {
    Bytes(u64),
    Samples(u64),
}

When to wake up asynchronous iterators.

“wake up” means notifying the async runtime to schedule the asynchronous iterator’s future to be pulled in the next round.

For performance reasons, we may not want to wake up asynchronous iterators as soon as data is available. With this option we can configure the number of bytes or samples that triggers the wake up.

If we specify the Proc instead of All, asynchronous iterators will be woken up when the target process exits.

Examples

use perf_event_open::config::{Cpu, Opts, Proc, SampleOn, WakeUpOn};
use perf_event_open::count::Counter;
use perf_event_open::event::sw::Software;

let event = Software::TaskClock;
let target = (Proc::ALL, Cpu(0));

let mut opts = Opts::default();
opts.sample_on = SampleOn::Freq(1000);
// Wake up asynchronous iterators on every sample.
opts.wake_up.on = WakeUpOn::Samples(1);

let counter = Counter::new(event, target, opts).unwrap();
let sampler = counter.sampler(5).unwrap();

counter.enable().unwrap();

let mut iter = sampler.iter().into_async().unwrap();
println!("{:-?}", iter.next().await);

Variants

Bytes(u64)

Wake up on every N bytes available.

Bytes(0) means never wake up.

Samples(u64)

Wake up on every N samples available.

Samples(0) means never wake up.

Trait Implementations

impl Clone for WakeUpOn

fn clone(&self) -> WakeUpOn

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for WakeUpOn

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for WakeUpOn

fn default() -> Self

Returns the “default value” for a type.