Re: question about the set tcp window size in iperf 1.6.3
On Mon, 2 Dec 2002, Chong Zhang wrote:
> Box A is connecting via CableModem!!!, BoxB is in a university connection
> via
> a high-speed education network. That's it!
> I'll move box A to another university later this week and give more tests...
Yeah the cable service provider may not be giving symmetric service, or
the loading of the cable network may be affecting the results.
> So if I setup the buffer size to the default value using -w option, should
> that disable the autotuning?
Yes, or to 1/2 the default if it does the doubling thing.
> Also, Linux autotuning sounds like a black box. Is that the web100/Net100
> project?
> On their web-site the patch is available for Linux 2.4.19. So if I don't
> use that patch,
> there is no autotuning, am I right?
Nope the web100/net100 projects are completely different than the Linux
autotuning.
> Or Linux has other algorithms? How could I know it's enabled or not?
Check out some of the links off the Iperf page about tuning. I am not sure
off hand where and if you can globally disable the autotuning in the
kernel.
My guess is that you are not getting symmetric service with your cable
modem, you can look into the autotuning and what not if you want though.
Kevin
--
Mitch Kutzko | mitch --at-- dast.nlanr.net | mitch --at-- ncsa.uiuc.edu | 217-333-1199
http://hobbes.ncsa.uiuc.edu/