Creating byte array without initializing with 0s

Question

For a network related framework I need a lot of byte[] buffers to read and write data. When creating a new byte array, the CLR will initialize all values with 0. For buffers used with streams, this seems to be unnecessary overhead:

var buffer = new byte[65536];

var read = await stream.ReadAsync(buffer, 0, buffer.Length);

Is there a way to create a byte[] array without initializing all values with 0 in C#? Probably by invoking a malloc style method? I'm sure this question has been answered, but I didn't find any clues to start with.

Answer 1

Thanks to mjwills link, I stumbled upon the ArrayPool<T> of System.Buffers:

static void Main(string[] args)
{
    var pool = ArrayPool<byte>.Create();

    var watch = new Stopwatch();
    watch.Start();

    Parallel.For(0, 1000000, (i) =>
    {
        //DoSomethingWithBuffers();
        DoSomethingWithPooledBuffers(pool);
    });

    Console.WriteLine(watch.ElapsedMilliseconds);
}

private static int DoSomethingWithBuffers()
{
    var buffer = new byte[65536];
    return buffer.Length;
}

private static int DoSomethingWithPooledBuffers(ArrayPool<byte> pool)
{
    var buffer = pool.Rent(65536);

    var length = buffer.Length;

    pool.Return(buffer);

    return length;
}

Which makes quite a difference (release mode):

• DoSomethingWithBuffers: 3264ms
• DoSomethingWithPooledBuffers: 470ms