Non blocking Poll based (slow) server

Server.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Net;
using System.Net.Sockets;
using System.IO;

namespace HttpConcurrentServer
{
    class Server
    {

        List<Socket> serverSockets;
        List<Socket> clientSockets;

        public Server(int port)
        {
            Socket server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            server.Blocking = false;

            IPEndPoint serverAddress = new IPEndPoint(IPAddress.Any, port);

            server.Bind(serverAddress);
            server.Listen(10);

            serverSockets = new List<Socket>();
            serverSockets.Add(server);

            clientSockets = new List<Socket>();
        }

        public void Run()
        {
            byte[] data = new byte[8192];

            while (true)
            {
                // iterate server sockets, checking for item in the backlog
                foreach (Socket socket in serverSockets)
                {
                    if (socket.Poll(0, SelectMode.SelectRead))
                    {
                        Socket newClient = socket.Accept();
                        Console.WriteLine("new client available");
                        // limit clients number
                        if (clientSockets.Count > 10)
                        {
                            newClient.Close();
                            continue;
                        }
                        clientSockets.Add(newClient);
                    }
                }

                List<Socket> deadClients = new List<Socket>();

                // now iterate clients
                foreach (Socket socket in clientSockets)
                {
                    if (socket.Poll(0, SelectMode.SelectRead))
                    {
                        int dataLength = socket.Receive(data);
                        if (dataLength <= 0)
                        {
                            socket.Close();
                            deadClients.Add(socket);
                            continue;
                        }

                        string httpData = Encoding.ASCII.GetString(data, 0, dataLength);
                        Console.WriteLine(httpData);
                    }
                }


                // remove dead clients
                foreach (Socket socket in deadClients)
                {
                    clientSockets.Remove(socket);
                }
            }
        }
    }
}