summaryrefslogtreecommitdiffstats
path: root/src/seastar/demos/udp_zero_copy_demo.cc
blob: a0d7733a35d1fd432037aa87940036300e12cf24 (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
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
/*
 * This file is open source software, licensed to you under the terms
 * of the Apache License, Version 2.0 (the "License").  See the NOTICE file
 * distributed with this work for additional information regarding copyright
 * ownership.  You may not use this file except in compliance with the License.
 *
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
/*
 * Copyright (C) 2014 Cloudius Systems, Ltd.
 */

#include <seastar/core/seastar.hh>
#include <seastar/core/app-template.hh>
#include <seastar/core/scattered_message.hh>
#include <seastar/core/vector-data-sink.hh>
#include <seastar/core/shared_ptr.hh>
#include <seastar/core/units.hh>
#include <seastar/core/timer.hh>
#include <seastar/net/api.hh>
#include <random>
#include <iomanip>
#include <iostream>

using namespace seastar;
using namespace net;
using namespace std::chrono_literals;
namespace bpo = boost::program_options;

template <typename Duration>
typename Duration::rep to_seconds(Duration d) {
    return std::chrono::duration_cast<std::chrono::seconds>(d).count();
}

class server {
private:
    udp_channel _chan;
    timer<> _stats_timer;
    uint64_t _n_sent {};
    size_t _chunk_size;
    bool _copy;
    std::vector<packet> _packets;
    std::unique_ptr<output_stream<char>> _out;
    steady_clock_type::time_point _last;
    sstring _key;
    size_t _packet_size = 8*KB;
    char* _mem;
    size_t _mem_size;
    std::mt19937 _rnd;
    std::random_device _randem_dev;
    std::uniform_int_distribution<size_t> _chunk_distribution;
private:
    char* next_chunk() {
        return _mem + _chunk_distribution(_rnd);
    }
public:
    server()
        : _rnd(std::random_device()()) {
    }
    future<> send(ipv4_addr dst, packet p) {
        return _chan.send(dst, std::move(p)).then([this] {
            _n_sent++;
        });
    }
    void start(int chunk_size, bool copy, size_t mem_size) {
        ipv4_addr listen_addr{10000};
        _chan = make_udp_channel(listen_addr);

        std::cout << "Listening on " << listen_addr << std::endl;

        _last = steady_clock_type::now();
        _stats_timer.set_callback([this] {
            auto now = steady_clock_type::now();
            std::cout << "Out: "
                << std::setprecision(2) << std::fixed
                << (double)_n_sent / to_seconds(now - _last)
                << " pps" << std::endl;
            _last = now;
            _n_sent = 0;
        });
        _stats_timer.arm_periodic(1s);

        _chunk_size = chunk_size;
        _copy = copy;
        _key = sstring(new char[64], 64);

        _out = std::make_unique<output_stream<char>>(
            data_sink(std::make_unique<vector_data_sink>(_packets)), _packet_size);

        _mem = new char[mem_size];
        _mem_size = mem_size;

        _chunk_distribution = std::uniform_int_distribution<size_t>(0, _mem_size - _chunk_size * 3);

        assert(3 * _chunk_size <= _packet_size);

        // Run sender in background.
        (void)keep_doing([this] {
            return _chan.receive().then([this] (udp_datagram dgram) {
                auto chunk = next_chunk();
                lw_shared_ptr<sstring> item;
                if (_copy) {
                    _packets.clear();
                    // FIXME: future is discarded
                    (void)_out->write(chunk, _chunk_size);
                    chunk += _chunk_size;
                    (void)_out->write(chunk, _chunk_size);
                    chunk += _chunk_size;
                    (void)_out->write(chunk, _chunk_size);
                    (void)_out->flush();
                    assert(_packets.size() == 1);
                    return send(dgram.get_src(), std::move(_packets[0]));
                } else {
                    auto chunk = next_chunk();
                    scattered_message<char> msg;
                    msg.reserve(3);
                    msg.append_static(chunk, _chunk_size);
                    msg.append_static(chunk, _chunk_size);
                    msg.append_static(chunk, _chunk_size);
                    return send(dgram.get_src(), std::move(msg).release());
                }
            });
        });
    }
};

int main(int ac, char ** av) {
    server s;
    app_template app;
    app.add_options()
        ("chunk-size", bpo::value<int>()->default_value(1024),
             "Chunk size")
        ("mem-size", bpo::value<int>()->default_value(512),
             "Memory pool size in MiB")
        ("copy", "Copy data rather than send via zero-copy")
        ;
    return app.run_deprecated(ac, av, [&app, &s] {
        auto&& config = app.configuration();
        auto chunk_size = config["chunk-size"].as<int>();
        auto mem_size = (size_t)config["mem-size"].as<int>() * MB;
        auto copy = config.count("copy");
        s.start(chunk_size, copy, mem_size);
    });
}