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Subject: Re: bandwidth for bkbits.net (good news)
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Andrea Arcangeli <andrea@suse.de>
Cc: Larry McVoy <lm@work.bitmover.com>, Larry McVoy <lm@bitmover.com>,
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       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Llu, 2003-09-01 at 00:22, Andrea Arcangeli wrote:
> the only difference I believe is that the connections are originated by
> my end, but that only changes the syn packet that normally accounts for
> a non significant amount of the bandwidth. And while this is located in
> a house, this isn't what I would call an home user usage.

Each ACK that has caused previous delays generally opens up a 64K window
so you get bursts of data incoming. A sequence of acks can cause the
incoming pipe to fill enough to screw up voip very easily.

Window bending stuff does help and certainly the packeteer boxes use it
to good effect. I've never tried that on Linux but even then Im dubious
that just cutting the routes down to an 8K window would help