TcpClient always got ReceiveBufferSize = 65536 on Windows 8.1

Question

I created a NetworkStream object and read bytes matches TcpClient's ReceiveBufferSize. It worked fine on Windows 7 but seemed have problems on Windows 8.1. As a result, I had to make my buffer size large enough, such as 65536 as title.

I don't think create this quite large size buffer in main loop is a good choice. Any suggestion ?

Thanks a lot.

[update]

I checked this page msdn-tcpclient.receivebuffersize and found that the default size is 8192. Maybe in fact the default size will be different in different platform.

So I just make it safer like this,

var client = tcpListener.AcceptTcpClient();
var data = new byte[client.ReceiveBufferSize];
client.GetStream().Read(data, 0, client.ReceiveBufferSize);

better ?

But my problem is not how to new an enough buffer size for reading purpose, my problem is why ReceiveBufferSize is set to 65536 on Windows 8.1, especially I didn't set manually just keep it default, or otherwise how can it work on Windows 7.

Answer 1

As far as I understand it now, ReceiveBufferSize doesn't actually get the size of the buffer, its just a way for you to set a size manually first, and use it later.

Looks like we're gonna have to set a fixed size here, with no way to get the size of the buffer before it's reading.

https://learn.microsoft.com/en-us/dotnet/api/system.net.sockets.tcpclient.receivebuffersize?view=net-5.0