I have been doing some performance testing with the new 4.2 Premium SDK on a Spider. I am seeing some great send speeds, the impressive news, and what appears to be a firmware exception.
The first performance testing involved sending from the Spider to a PC program. The PC was a virtual machine, running under Fusion on an IMac.
The Spider program, which used the Premium library, not Gadgeteer, got a network address via DHCP, and then established a connection to the PC program. After the connection was established, the Spider looped sending fixed length buffer to the PC.
The PC, with a 34KB input buffer, did a read to its 32KB buffer, counted bytes received, and every ten seconds calculated the bytes per second receive rate.
The results:
For a 1024 byte send buffer on the Spider, the PC receive rate was arount 590KBS, or 4.7 Mbs.
For a 8192 byte send buffer on the Spider, the PC rate was 1,175KBS, or 9.4 Mbs.
For a 16384 byte send buffer on the Spider, the PC rate was 1,245KBS, or ~10 Mbs.
These are impressive rates.
I then decided to see what the rate would be if I went with a small buffer. I choose
a 512 send buffer. No go. I am getting the following displayed on the
T35 LCS:
cps=0x200000df
pc=0x000049f0
ir=0x00000000
sp=0x4000efa8
Looks like a firmware exception?
Following are the programs I used for the test
PC PROGRAM
using System;
using System.Net;
using System.Net.Sockets;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace TCPReceiver
{
class Program
{
// Listening on port 20000
// assumes Ethernet cable is inserted
static void Main(string[] args)
{
TimeSpan tenSeconds = new TimeSpan(0, 0, 10);
IPEndPoint listenEP = new IPEndPoint(IPAddress.Any, 20000);
Socket listenSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
listenSocket.Bind(listenEP);
listenSocket.Listen(5);
while (true)
{
Console.WriteLine("Waiting for connection...");
Socket sessionSocket = listenSocket.Accept();
Console.WriteLine("Connection from {0}", sessionSocket.RemoteEndPoint);
byte[] buffer = new byte[1024];
DateTime start = DateTime.Now;
int totalBytesRead = 0;
while (true)
{
try
{
int bytesRead = sessionSocket.Receive(buffer);
if (bytesRead == 0)
break;
TimeSpan elapsed = DateTime.Now - start;
totalBytesRead += bytesRead;
if (elapsed >= tenSeconds)
{
int bytesPerSecond = (int)(totalBytesRead / (elapsed.TotalMilliseconds / 1000.0));
Console.WriteLine(bytesPerSecond);
totalBytesRead = 0;
start = DateTime.Now;
}
}
catch (Exception)
{
break;
}
}
Console.WriteLine("Connection terminated");
}
}
}
}
Spider/EMX Program
using System;
using System.Net;
using System.Net.Sockets;
using System.Threading;
using Microsoft.SPOT;
using Microsoft.SPOT.Hardware;
using GHI.Premium.Net;
namespace TCPTransmitter
{
public class Program
{
// assumes cable is inserted to reduce code to minimum
private static EthernetBuiltIn Eth1 = new EthernetBuiltIn();
private static AutoResetEvent ipAddressReady = new AutoResetEvent(false);
private static byte[] buffer = new byte[512];
public static void Main()
{
Eth1.Open();
NetworkInterfaceExtension.AssignNetworkingStackTo(Eth1);
Eth1.NetworkAddressChanged += new NetworkInterfaceExtension.NetworkAddressChangedEventHandler(Eth1_NetworkAddressChanged);
Eth1.NetworkInterface.EnableDhcp();
// wait for ip address
ipAddressReady.WaitOne();
Debug.Print("Got IP Address");
Socket socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPAddress ipAddress = IPAddress.Parse("192.168.1.10");
IPEndPoint remoteEP = new IPEndPoint(ipAddress, 20000);
Debug.Print("Starting connect");
socket.Connect(remoteEP);
Debug.Print("Connected");
int bytesSent = 0;
while (true)
{
bytesSent += socket.Send(buffer);
}
}
static void Eth1_NetworkAddressChanged(object sender, EventArgs e)
{
if (Eth1.NetworkInterface.IPAddress != "0.0.0.0")
ipAddressReady.Set();
}
}
}