Re: W/RTT verification, linux tcp buffers behaviour

From: Angelo P. Castellani
Date: Tue May 16 2006 - 10:05:41 EST

On 5/16/06, Constantinos Makassikis <cmakassikis@xxxxxxxxx> wrote:
I don't really understand what those 10 MB are.

because that limits the maximum SO_SNDBUF (and RCV) value you can give
to the kernel, anyway i've keeped a little margin because some progs
change the value you pass them doing the setsockopt

i think you can safely ignore/reduce the margin (and also divide by 2)

anyway it doesn't cause any problem/error

How is cwnd measured ?

take a look at

Besides those settings, were there any tcp buffers set manually (via
setsockopt()) ?

no, because the buffer, if needed, auto-grows until max size is reached

Could you give me more details about the machines' configuration as
well as the underlying network ?

they've gigabit ethernet cards, the latency between them is changed using netem

Angelo P. Castellani
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