summaryrefslogtreecommitdiffstats
path: root/benches/latency.rs
blob: 5b73d44a99ef69cb6ae08bb0e951e879ba59d92a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
#![feature(test)]

extern crate test;
extern crate futures;
#[macro_use]
extern crate tokio_core;

use std::io;
use std::net::SocketAddr;

use futures::{Future, Poll, Sink, Stream};
use tokio_core::net::UdpSocket;
use tokio_core::reactor::Core;
use tokio_core::channel::Sender;

use test::Bencher;
use std::thread;

use futures::sync::oneshot;

/// UDP echo server
struct EchoServer {
    socket: UdpSocket,
    buf: Vec<u8>,
    to_send: Option<(usize, SocketAddr)>,
}

impl EchoServer {
    fn new(s: UdpSocket) -> Self {
        EchoServer {
            socket: s,
            to_send: None,
            buf: vec![0u8; 1600],
        }
    }
}

impl Future for EchoServer {
    type Item = ();
    type Error = io::Error;

    fn poll(&mut self) -> Poll<(), io::Error> {
        loop {
            if let Some(&(size, peer)) = self.to_send.as_ref() {
                try_nb!(self.socket.send_to(&self.buf[..size], &peer));
                self.to_send = None;
            }
            self.to_send = Some(try_nb!(self.socket.recv_from(&mut self.buf)));
        }
    }
}

#[bench]
fn udp_echo_latency(b: &mut Bencher) {
    let any_addr = "127.0.0.1:0".to_string();
    let any_addr = any_addr.parse::<SocketAddr>().unwrap();

    let (stop_c, stop_p) = oneshot::channel::<()>();
    let (tx, rx) = oneshot::channel();

    let child = thread::spawn(move || {
        let mut l = Core::new().unwrap();
        let handle = l.handle();

        let socket = tokio_core::net::UdpSocket::bind(&any_addr, &handle).unwrap();
        tx.complete(socket.local_addr().unwrap());

        let server = EchoServer::new(socket);
        let server = server.select(stop_p.map_err(|_| panic!()));
        let server = server.map_err(|_| ());
        l.run(server).unwrap()
    });


    let client = std::net::UdpSocket::bind(&any_addr).unwrap();

    let server_addr = rx.wait().unwrap();
    let mut buf = [0u8; 1000];

    // warmup phase; for some reason initial couple of
    // runs are much slower
    //
    // TODO: Describe the exact reasons; caching? branch predictor? lazy closures?
    for _ in 0..8 {
        client.send_to(&buf, &server_addr).unwrap();
        let _ = client.recv_from(&mut buf).unwrap();
    }

    b.iter(|| {
        client.send_to(&buf, &server_addr).unwrap();
        let _ = client.recv_from(&mut buf).unwrap();
    });

    stop_c.complete(());
    child.join().unwrap();
}

#[bench]
fn channel_latency(b: &mut Bencher) {
    let (tx, rx) = oneshot::channel();

    let child = thread::spawn(move || {
        let mut l = Core::new().unwrap();
        let handle = l.handle();

        let (in_tx, in_rx) = tokio_core::channel::channel(&handle).unwrap();
        let (out_tx, out_rx) = tokio_core::channel::channel(&handle).unwrap();
        tx.complete((in_tx, out_rx));

        let server = out_tx.send_all(in_rx);

        l.run(server).unwrap();
    });

    let (in_tx, out_rx) = rx.wait().unwrap();
    let mut rx_iter = out_rx.wait();

    // warmup phase; for some reason initial couple of runs are much slower
    //
    // TODO: Describe the exact reasons; caching? branch predictor? lazy closures?
    for _ in 0..8 {
        Sender::send(&in_tx, 1usize).unwrap();
        let _ = rx_iter.next();
    }

    b.iter(|| {
        Sender::send(&in_tx, 1usize).unwrap();
        let _ = rx_iter.next();
    });

    drop(in_tx);
    child.join().unwrap();
}