From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [RFC] tcp: use order-3 pages in tcp_sendmsg()
Date: Fri, 21 Sep 2012 18:51:21 +0200
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To: David Miller <davem@davemloft.net>
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On Fri, 2012-09-21 at 12:27 -0400, David Miller wrote:
> From: Eric Dumazet <eric.dumazet@gmail.com>
> Date: Fri, 21 Sep 2012 17:48:31 +0200
> 
> > There is probably a reason why lo default MTU is 16436 ?
> 
> That's what fit into L1 caches back in 1999

I see ;)

Nowadays, we even have the NETIF_F_NOCACHE_COPY flag and
__copy_from_user_nocache()

Hmm, we can not toggle this flag on loopback yet

# ethtool -K lo tx-nocache-copy on
Could not change any device features