From mboxrd@z Thu Jan  1 00:00:00 1970
From: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Subject: Re: [PATCH] ipv6: Limit mtu to 65572 bytes
Date: Fri, 11 Apr 2014 11:30:44 +0900
Message-ID: <534753D4.6070600@linux-ipv6.org>
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Cc: Francois WELLENREITER <f.wellenreiter@gmail.com>,
	netdev@vger.kernel.org, YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
To: Eric Dumazet <eric.dumazet@gmail.com>,
	Hannes Frederic Sowa <hannes@stressinduktion.org>,
	David Miller <davem@davemloft.net>
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Eric Dumazet wrote:

> We must limit the IPv6 MTU to (65535 + 40) bytes in theory.
> 
> In practice, its better to align to a multiple of 4 for optimal TCP
> performance.

It is a TCP issue.  We should not limit the mtu to 65532+40.
I am for 65535+40. Otherwise, other protocol such as UDP cannot
use full mtu as before.

--yoshfuji