Slow download on Mac and Linux using sockets

Question

We have a need to download as much as possible for a couple seconds using sockets, and we have noticed that Adobes flash player on Mac and Linux are slower then Windows while we get good results on all tree OS using Goggles flash player in Chrome.
Our setup, client side, is a 1 Gbit/s internet connection throttle by a 100 Mbit/s switch. On the server side, we have an Apache web server (during testing) on a 1 Gbit/s internet connection.
For testing purposes, we download as much as possible of a 2 Gb big file for approximately 10 seconds. After we connect to the server, via a socket, we send an http request to start downloading the file. Using bytesAvailable, we get the number of bytes downloaded every half second, calculate the average speed for that half second and store that value in an array. After 20 times, we stop downloading and close the socket connection. Finally we calculate the average download speed of the 20 measurements.
All tests are preformed on version 11.6.602.180 except for Adobe Flash player on Ubuntu were the 11.2 r202 version. Adobe Flash player on Firefox 19.0.2 (other browsers were tested with similar results) and Google Flash player on Chrome 26.0.1410.43. Each OS/player was tested 5 times and presents the average.
Windows 7 Enterprise (64-bit) 
Mac OS X 10.6.8 (64 bit) 
Ubuntu 12.10 (64 bit) 
Adobe Flash player (NPSWF32_11_6_602_180.dll)
92.73 Mbit/s 
14.53 Mbit/s 
44.25 Mbit/s 
Google Flash player (pepflashplayer.dll)
91,89 Mbit/s 
89.46 Mbit/s 
91.57 Mbit/s 
doConnect();
function doConnect():void {
    socket = new Socket(url,port);
    socket.addEventListener(Event.CONNECT, connectHandler);
function connectHandler(event:Event):void {
    writeln("GET " + path + " HTTP/1.1");
    writeln("Host: " + url);
    writeln("Connection: close");
    writeln("");
    nStart = new Date().time;
    startTimer();
    socket.flush();
function writeln(str:String):void {
    str +=  "\n";
    socket.writeUTFBytes(str);
function startTimer(){
    startTime = new Date().time;
    var myTimer:Timer = new Timer(500,20);// 0.5 seconds 20 times
    myTimer.addEventListener(TimerEvent.TIMER, timeMeasurement);
    myTimer.addEventListener(TimerEvent.TIMER_COMPLETE, timeMeasurementComplete);
    myTimer.start();
function timeMeasurement():void {
    receivedData = socket.bytesAvailable;
    var varJunk:ByteArray = new ByteArray();
    while (socket.bytesAvailable > 4){
        socket.readBytes(varJunk);
    var split:Number = new Date().time - startTime;
    var speed:Number = receivedData * 8 / ((new Date().time - startTime) / 1000);
    startTime = new Date().time;
    downloadList.push(speed);
    receivedData = 0;
function timeMeasurementComplete():void{
    var len:int = downloadList.length;
    var sum:Number = 0;
    for (var i:int = 0; i < len ; i++) {
        sum +=  downloadList[i];
    downloadResult = sum / len;
    socket.removeEventListener(Event.CONNECT, connectHandler);
    if(socket.connected){
        socket.close();
In further investigation we built an easy Flash based latency meter. We download a small txt-file, measuring the time between just before we send http-request and until we receive a response from the web server.
We have the setup as for the speed tests, but we do this 5 * 20 times with each OS/player.
Windows 7 Enterprise (64-bit) 
Mac OS X 10.6.8 (64 bit) 
Ubuntu 12.10 (64 bit) 
Adobe Flash player 
4.30 ms 
66.67 ms 
10.49 ms 
Google Flash player 
4.25 ms 
4.28 ms 
4.19 ms 
doConnect();
private function doConnect():void{
    socket = new Socket(url,port);
    socket.addEventListener(Event.CONNECT, connectHandler);
    socket.addEventListener(ProgressEvent.SOCKET_DATA, socketDataHandler);
private function connectHandler(event:Event):void{
    writeln("GET " + path + " HTTP/1.1");
    writeln("Host: " + url);
    socket.flush();
    nStart = new Date().time;
private function writeln(str:String):void{
    str +=  "\n";
    socket.writeUTFBytes(str);
private function socketDataHandler(event:ProgressEvent):void{
    var latecy:Number = new Date().time - nStart; // latency in ms
Using a packet analyzer (Wireshark) on the OS X/Adobe player, the time from http-request is sent to data is received is approximately 2 ms. An ack is sent less then 0.04 ms after the packet is received. Using the socketData event to send a new http-request, just after we measure the time for the last package, can see event created delays. We have a delay between 64 and 67 ms compare that to OS X/Google player with between 1 and 3 ms delay.
Note: When playing around a timer, that fired a number of times during parts of a large number of latency measurements, we notice that measurements when the timer was running were better. Testing having a empty timer firing as fast as possible constantly during both download and latency measurements we got significantly better results on OS X/Adobe player, although not good. Average download 31,82 Mbit/s and average latency 16,59 ms.

Answer 1

Bumping this topic again as it's still sort of bugging me, but the problem has been isolated to a few certain sites. On some i get the maximum speed and on others i get snailspeed. One of the slow ones unfortunately is basically anything that has to do with Apple....So all Quicktime movie trailers, iTunes stuff, movies etc are slow, except podcasts that are German. I'm downloading the 30 day trial of iWork and i'm getting whopping 19,2KB/s, when i should be getting about 1300KB/s. You can just imagine the frustration:/
I'm just wondering am i alone on this or is anybody else excperienceing similar? And as usual, on windows i'm getting full speed all the time, anywhere, grrrr....!
-CC