Quote:
Originally Posted by Andrewcrawford23
ive done some tests to check apart from it a pain in the back side to really change the windows size in linux and windows as they use automatic calculatiosn to adjsut window size to what ti sees as best.... but i did see a difference in ping acklodegements by about 10-20ms but its intial test i will really need to benchmark it witha a clena system and remove all other variables until then ill agree with you it probally doesnt affect
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I had 10 minutes.
Here's how the latency test used by Speedtest.net works - the app requests a file called latency.txt from the server with a parameter specific to that test:
GET /speedtest/latency.txt?x=1325619351882 HTTP/1.1
Host:
www.speedtest.bbmax.co.uk
Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.7 (KHTML, like Gecko) Chrome/16.0.912.63 Safari/535.7
Accept: */*
Referer:
http://c.speedtest.net/flash/speedtest.swf?v=297277
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-GB,en-US;q=0.8,en;q=0.6
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
The server responds:
HTTP/1.1 200 OK
Date: Tue, 03 Jan 2012 19:36:07 GMT
Server: Apache/2.2.3 (CentOS)
Last-Modified: Fri, 29 Sep 2006 15:09:15 GMT
ETag: "cc01f2-a-a17bcc0"
Accept-Ranges: bytes
Content-Length: 10
Connection: close
Content-Type: text/plain; charset=UTF-8
test=test
It does this a few times.
The app does some kind of timing between the two. Window size is a complete non-issue as the window is at no point approached and more relevantly as I said window sizes don't work like that. Nagle might be more of a factor as the app will send its request which will then sit on the TCP stack of the host machine waiting for a full MSS of data to be sent.
334 6.001751 192.168.10.12 85.233.160.167 HTTP GET /speedtest/latency.txt?x=1325619351882 HTTP/1.1
Frame 334: 489 bytes on wire (3912 bits), 489 bytes captured (3912 bits)
Arrival Time: Jan 3, 2012 19:35:51.980248000 GMT Standard Time
337 6.021832 85.233.160.167 192.168.10.12 HTTP HTTP/1.1 200 OK (text/plain)
Frame 337: 325 bytes on wire (2600 bits), 325 bytes captured (2600 bits)
Arrival Time: Jan 3, 2012 19:35:52.000329000 GMT Standard Time