test.cs

using System;
using System.Diagnostics;
using System.Threading;

public class Program
{
    const int NUM_REFS = 200;
    const int NUM_ALIVES = 200000;

    static Stopwatch st = new Stopwatch ();
    static object[] objects = new object [NUM_REFS];
    static WeakReference[] weak_refs = new WeakReference [NUM_REFS];

    public static void Time1 ()
    {
        int i, alive = 0;
        for (i = 0; i < NUM_REFS * NUM_ALIVES * 10; i++) {
            if ((alive & 0xff) == 0)
                alive++;
        }
        Console.WriteLine ("{0}", alive);
    }

    public static int Time2 ()
    {
        int alive = 0;
        for (int i = 0; i < NUM_REFS; i++) {
            for (int j = 0; j < NUM_ALIVES; j++) {
                if (weak_refs [i].IsAlive)
                    alive++;
            }
        }
        return alive;
    }

    public static void Init ()
    {
        st.Reset ();
        st.Start ();
        for (int i = 0; i < NUM_REFS; i++) {
            objects [i] = i;
            weak_refs [i] = new WeakReference (objects [i]);
        }

        Time1 ();
        st.Stop ();
        Console.WriteLine ("Init {0} ms", st.ElapsedMilliseconds);

    }

    public static void Run ()
    {
        int alive;

        st.Reset ();
        st.Start ();
        alive = Time2 ();
        st.Stop ();
        Console.WriteLine ("Bench {0} ms, alive {1}", st.ElapsedMilliseconds, alive);
    }

    public static void Main ()
    {
        Init ();
        Run ();
    }
}