From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [RFC] [TCP 1/3] tcp: Add MSG_NEW_PACKET flag to indicate
 preferable packet boundaries
Date: Fri, 29 Jun 2012 19:15:57 +0200
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Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	Herbert Xu <herbert@gondor.apana.org.au>,
	"David S. Miller" <davem@davemloft.net>
To: Andreas Gruenbacher <agruen@linbit.com>
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On Fri, 2012-06-29 at 17:38 +0200, Andreas Gruenbacher wrote:

> The primary use case is fast Gigabit (10 or more) Ethernet connections
> with jumbo frames and switches that support them.  There, frames will go
> through unchanged and you can zero-copy receive all the time.
> 
> Not sure how well the approach scales to other kinds of connections; it
> may work often enough to be worth it.  When things get distorted between
> the sender and the receiver and tcp_recvbio() fails, the data can still
> be copied out of the socket as before.

If you have a packet loss, receiver can and will coalesce frames.