Re[2]: tcp_window_scaling degrades performance

From: Maciej Soltysiak
Date: Fri Jul 16 2004 - 05:22:43 EST

AK> It's pretty easy for you to find out. Do a tcpdump -v or ethereal -v
AK> from both the side of a host you download from and from the linux side.
AK> Then compare all packets. If they don't match the firewall is
AK> doing something bad. Especially check window values and TCP options
AK> in the SYN packets
I will do that for sure, but preliminary investigation shows that
this behaviour does not show with 2.6.7 and earlier, but appears for sure in
2.6.7-bk13 (Haven't tried earlier bk snapshots)

AK> It is very very likely the firewall, window scaling works for a lot
AK> of people.
It is probable, but here: only 2.6.7+ machines behave like this.
I also noticed, that turning tcp_window_scaling off does not always
fix the problem, turning tcp_bic to 0 too helps even more.


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