From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: Major network performance regression in 3.7
Date: Sat, 05 Jan 2013 18:44:15 -0800
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Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org
To: Willy Tarreau <w@1wt.eu>
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On Sun, 2013-01-06 at 03:32 +0100, Willy Tarreau wrote:

> It's 0cf833ae (net: loopback: set default mtu to 64K). And I could
> reproduce it with 3.6 by setting loopback's MTU to 65536 by hand.
> The trick is that once the MTU has been set to this large a value,
> even when I set it back to 16kB the problem persists.
> 

Well, this MTU change can uncover a prior bug, or make it happen faster,
for sure.