I normally wouldn't ask these questions (and I do apologize),
but since your data source is labeled as being an http server:
Are you convinced that you are passing enough data during the life
of the measured TCP connections to allow your congestion window to
fully open?
If yes, are you passing enough *additional* data to make the
time spent in slow-start negligible when calculating the average
throughput of the connection?
How large are your test data flows?
Tuning the TCP connection parameters is important, but that
can only remove artificial bounds on performance. You still
need to allow for TCP to probe for the capacity of the path;
It could be that you simply aren't transferring enough data...
Eric
Eric Travis
[email protected]
On Mon, 28 May 2001, Dusan Statelov wrote:
> Hello:
>
> As we are now in time pressure I would like ask you for advices how to
> properly configure Win2000 or Linux Http data server in order to achieve
> bigger TCP window and improve Single TCP connection from poor 20-30
> kbyte/s (for RTT 240 ms) to according to us achievable 1 mbps.
> We have changed "Default Receive Window", but TCP is running at only
> 20-30 kbyte/s what would corresponde to 8 kbyte Window rather then to 64
> kbyte.
> I assume there are other TCP registry entities which influence Sender
> Window.
>
> Here is a configuration emulating satellite internet:
>
> Http Data Server [Linux or Win2000] -> DVB/ip -> DVB-S Modulator -> L
> band output -> PC DVB board [SkyMedia - Telemann, TT DVB Technotrend] ->
>
> client PC [Win98] o---------------o connected to DVB/ip GW in return
> via LAN
> LAN RTT 20 ms
> Artefficial delay in DVB/ip GW 220 ms (in order to simulate long RTT for
> satellite)
>
> Windows98
> Default Receive Window to max.values 65535
> Data Sever Win2000
> Default Receive Window to max.values 65535 (we tried even 0,5 Mbyte with
> no effect)
> RTT 240 ms
> Single TCP connection 20 - 30 kbyte/s
>
> Thanks in advance.
>
> Dusan Statelov
> Managing Director
> Main Data,s.r.o.
> mailto:[email protected]
>
> Tel: +421 7 54789 586
> Fax: +421 7 54789 585
> GSM: +421 905 606 027
> http://www.maindata.sk
>
>
This archive was generated by hypermail 2b29 : Mon May 28 2001 - 16:46:03 EDT