#![feature(test)]
extern crate futures;
extern crate futures_channel;
extern crate futures_executor;
extern crate test;
use futures::prelude::*;
use futures::future;
use futures::stream::FuturesUnordered;
use futures_channel::oneshot;
use futures_executor::block_on;
use test::Bencher;
use std::collections::VecDeque;
use std::thread;
#[bench]
fn oneshots(b: &mut Bencher) {
const NUM: usize = 10_000;
b.iter(|| {
let mut txs = VecDeque::with_capacity(NUM);
let mut rxs = FuturesUnordered::new();
for _ in 0..NUM {
let (tx, rx) = oneshot::channel();
txs.push_back(tx);
rxs.push(rx);
}
thread::spawn(move || {
while let Some(tx) = txs.pop_front() {
let _ = tx.send("hello");
}
});
let f = future::poll_fn(move |cx| {
loop {
if let Ok(Async::Ready(None)) = rxs.poll_next(cx) {
break
}
}
Ok::<_, ()>(Async::Ready(()))
});
block_on(f).unwrap();
});
}