I’m trying to set up a single server single client connection in golang,
The goal is is to perform the fastest connection between the server and the client
The rate from server to client need to be enough for full hd video transfer at 60 fps (around 30Mbps once frames are compressed)

My actual transfer rate with the following snippets are around 11 Mbps with Ethernet and 6 Mbps for WiFi

I’ve settled up a multi channels video sending for both client and server, the server channels effectively speed up the rate by 2 over WiFi but channels for the client don’t help at all actually, which is logic given the nature of the code used by the client side channels

The goal of the following code is to perform the fastest possible transfert using websocket from the server to the client

main.go (server) =>

package main

import (
    "fmt"
    "log"
    "net/http"
    "sync"
    "time"

    "github.com/gorilla/websocket"
)

var upgrader = websocket.Upgrader{
    CheckOrigin: func(r *http.Request) bool {
        return true
    },
}

type Channel struct {
    name      string
    buffer    chan []byte
    bytesSent int
    mu        sync.Mutex
}

type Server struct {
    clients   map[*websocket.Conn]bool
    broadcast chan []byte
    channels  map[string]*Channel
    mu        sync.Mutex
}

func newServer() *Server {
    return &Server{
        clients:   make(map[*websocket.Conn]bool),
        broadcast: make(chan []byte),
        channels:  make(map[string]*Channel),
    }
}

func (s *Server) handleConnections(w http.ResponseWriter, r *http.Request) {
    ws, err := upgrader.Upgrade(w, r, nil)
    if err != nil {
        log.Fatalf("Failed to upgrade to WebSocket: %v", err)
    }
    defer ws.Close()

    s.mu.Lock()
    s.clients[ws] = true
    s.mu.Unlock()

    for {
        _, msg, err := ws.ReadMessage()
        if err != nil {
            log.Printf("Error reading message: %v", err)
            delete(s.clients, ws)
            break
        }
        s.broadcast <- msg
    }
}

func (s *Server) handleMessages() {
    for {
        msg := <-s.broadcast
        for client := range s.clients {
            err := client.WriteMessage(websocket.BinaryMessage, msg)
            if err != nil {
                log.Printf("Error writing message: %v", err)
                client.Close()
                delete(s.clients, client)
            }
        }
    }
}

func (s *Server) createChannel(name string) {
    s.mu.Lock()
    defer s.mu.Unlock()
    if _, exists := s.channels[name]; !exists {
        s.channels[name] = &Channel{name: name, buffer: make(chan []byte, 100)}
    }
}

func (s *Server) startChannel(name string) {
    s.mu.Lock()
    channel, exists := s.channels[name]
    s.mu.Unlock()
    if !exists {
        log.Printf("Channel %s does not exist", name)
        return
    }

    go func() {
        for msg := range channel.buffer {
            s.broadcast <- append([]byte(name+": "), msg...)
            channel.mu.Lock()
            channel.bytesSent += len(msg)
            channel.mu.Unlock()
        }
    }()
}

func (s *Server) sendToChannel(name string, msg []byte) {
    s.mu.Lock()
    channel, exists := s.channels[name]
    s.mu.Unlock()
    if !exists {
        log.Printf("Channel %s does not exist", name)
        return
    }
    channel.buffer <- msg
}

func main() {
    server := newServer()

    http.HandleFunc("/ws", server.handleConnections)

    go server.handleMessages()

    numChannels := 10 // Number of channels
    for i := 1; i <= numChannels; i++ {
        channelName := fmt.Sprintf("channel_%d", i)
        server.createChannel(channelName)
        server.startChannel(channelName)
    }

    // Queue for distributing data
    dataQueue := make(chan []byte, 1000)

    // Generate dummy data
    go func() {
        dummyData := make([]byte, 512*1024)             // 0.5 MB of dummy data
        ticker := time.NewTicker(time.Millisecond * 17) // 60 times per second
        for {
            select {
            case <-ticker.C:
                dataQueue <- dummyData
            }
        }
    }()

    // Distribute data among channels
    go func() {
        channelId := 1
        for data := range dataQueue {
            channelName := fmt.Sprintf("channel_%d", channelId)
            server.sendToChannel(channelName, data)
            channelId++
            if channelId > numChannels {
                channelId = 1
            }
        }
    }()

    // Log the total sent data every second
    go func() {
        ticker := time.NewTicker(1 * time.Second)
        defer ticker.Stop()
        for range ticker.C {
            totalSent := 0
            for _, channel := range server.channels {
                channel.mu.Lock()
                totalSent += channel.bytesSent
                channel.bytesSent = 0 // reset for the next second
                channel.mu.Unlock()
            }
            log.Printf("Total Sent: %.2f MB/s", float64(totalSent)/1024/1024)
        }
    }()

    log.Println("Server started on :8080")
    err := http.ListenAndServe(":8080", nil)
    if err != nil {
        log.Fatalf("Server failed to start: %v", err)
    }
}

main.go (client)

package main

import (
    "log"
    "net/url"
    "sync"
    "time"

    "github.com/gorilla/websocket"
)

type ChannelStats struct {
    sync.Mutex
    bytesReceived int
}

func readFromWebSocket(u url.URL, messageChan chan []byte, done chan bool) {
    u.Path = "/ws"
    c, _, err := websocket.DefaultDialer.Dial(u.String(), nil)
    if err != nil {
        log.Fatalf("Dial error: %v", err)
    }
    defer c.Close()

    for {
        _, message, err := c.ReadMessage()
        if err != nil {
            log.Printf("Read error: %v", err)
            done <- true
            return
        }
        messageChan <- message
    }
}

func processMessages(stats *ChannelStats, messageChan chan []byte, wg *sync.WaitGroup, done chan bool) {
    defer wg.Done()

    for {
        select {
        case message := <-messageChan:
            stats.Lock()
            stats.bytesReceived += len(message)
            stats.Unlock()
        case <-done:
            return
        }
    }
}

func main() {
    u := url.URL{Scheme: "ws", Host: "192.168.0.86:8080"}
    var wg sync.WaitGroup
    done := make(chan bool)
    messageChan := make(chan []byte, 100) // Buffered channel to hold messages
    stats := &ChannelStats{}
    numWorkers := 10 // Number of worker goroutines

    // Start a single reader goroutine
    go readFromWebSocket(u, messageChan, done)

    // Start multiple worker goroutines
    for i := 0; i < numWorkers; i++ {
        wg.Add(1)
        go processMessages(stats, messageChan, &wg, done)
    }

    // Log stats every second
    go func() {
        for {
            time.Sleep(1 * time.Second)
            stats.Lock()
            totalReceived := stats.bytesReceived
            stats.bytesReceived = 0 // reset for the next second
            stats.Unlock()
            log.Printf("Total Received: %.2f MB/s", float64(totalReceived)/1024/1024)
        }
    }()

    // Wait for all workers to finish
    wg.Wait()
    close(done)
}

I’m open to suggestions about the technology/library used to perform this data transfer, keeping in mind the goal is simply to perform the fastest data transfer in golang