From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: Slow speed of tcp connections in a network namespace
Date: Sat, 29 Dec 2012 13:12:26 -0800
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To: Andrew Vagin <avagin@parallels.com>
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On Sun, 2012-12-30 at 00:08 +0400, Andrew Vagin wrote:

> Is it right, that a received window will be less, if packets are not sorted?
> Looks like a bug.

Not really a bug.

TCP is very sensitive to packet reorders. I wont elaborate here as
its a bit off topic.

Try to reorders credits/debits on your bank account, I am pretty sure
you'll lose some money or even get serious troubles.

Of course, enabling GRO on eth0 would definitely help a bit...

(once/iff veth driver features are fixed to allow GSO packets being
forwarded without being segmented again)