using System;
using System.Diagnostics;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Runtime.InteropServices;

class A
{
    static int Main(string[] args)
    {
	try
	{
	    int period = 5;
	    int tolerate = 8;

	    using (Socket sock = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp))
	    {
		int port = 50040;

		sock.Connect(IPAddress.Loopback, port);

		NativeHigh(period, tolerate, sock);
	    }
	}
	catch (Exception ex)
	{
	    Console.Error.WriteLine(ex);
	}

	return 0;
    }

    static void NativeHigh(int period, int tolerate, Socket sock)
    {
	var t = CreateWaitableTimerEx(null, null, CREATE_WAITABLE_TIMER_HIGH_RESOLUTION, TIMER_ALL_ACCESS);

	SetWaitableTimer(t, 0, period, null, IntPtr.Zero, false);

	Stopwatch timer = Stopwatch.StartNew();

	const int ms = 10000;

	for (int i = 0; ; i++)
	{
	    WaitForSingleObject(t, INFINITE);

	    var n = timer.ElapsedTicks;
	    timer.Restart();

	    sock.Send(new byte[i % 1400 + 1]);

	    if (n > period * ms + tolerate * ms / 2) Console.WriteLine("{0} {1}", i, n);

	    if (n > period * ms + tolerate * ms) break;
	}

	CancelWaitableTimer(t);

	CloseHandle(t);
    }

    [DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
    static extern IntPtr CreateWaitableTimerEx(SECURITY_ATTRIBUTES sa, string name, uint flags, uint access);

    [DllImport("kernel32.dll", SetLastError = true)]
    static extern bool SetWaitableTimer(IntPtr h, in ulong due, int period, TIMERAPCROUTINE cb, IntPtr ctxt, bool resume);

    [DllImport("kernel32.dll", SetLastError = true)]
    static extern bool CancelWaitableTimer(IntPtr h);

    [DllImport("kernel32.dll", SetLastError = true)]
    static extern uint WaitForSingleObject(IntPtr h, uint ms);

    [DllImport("kernel32.dll", SetLastError = true)]
    static extern bool CloseHandle(IntPtr h);

    delegate void TIMERAPCROUTINE(IntPtr ctxt, uint lo, uint hi);

    const uint CREATE_WAITABLE_TIMER_HIGH_RESOLUTION = 0x00000002;

    const uint INFINITE = ~0U;

    const uint TIMER_ALL_ACCESS = 0x001F0003;
}

[StructLayout(LayoutKind.Sequential)]
class SECURITY_ATTRIBUTES {}