问无法使用备用内存

EN

static List<string> _str = new List<string>();
static int fill = 10000;
static int _remainingMemory = 50;

static void Main(string[] args)
{
    fillString();

    Console.ReadLine();
}

static void fillString()
{
    long count = 0;
    while (true)
    {
        try
        {
            if (++count % 500 == 0 || fill == 1)
            {
                ShowMemory();
            }

            _str.Add(new string('_', fill));
        }
        catch (OutOfMemoryException)
        {
            if (fill > 1)
            {                                         
                fill = 1;
            }
            else
            {
                Console.WriteLine("Not consuming memory...");
                return;
            }
        }
    }
}

private static void ShowMemory()
{
    System.Diagnostics.PerformanceCounter ramCounter;

    ramCounter = new System.Diagnostics.PerformanceCounter("Memory", "Available MBytes");
    Console.WriteLine("Memory Remaining: {0}", ramCounter.RawValue);
}