From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: zero copy for relay server
Date: Tue, 29 Mar 2011 16:13:37 +0200
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Cc: Viral Mehta <Viral.Mehta@lntinfotech.com>,
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To: Changli Gao <xiaosuo@gmail.com>
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Le mardi 29 mars 2011 =C3=A0 19:28 +0800, Changli Gao a =C3=A9crit :

> It is a waste of fd using pipe buffer with two fds. In fact, I had
> ever posted a patch, which extends pipe(2) to return a O_RDWR fd when
> NULL is passed in.
>=20

Oh well, one extra fd is less than 256 bytes.

Adding a syscall means you force users to have latest kernel.

All this is hypothetical, nobody gave performance numbers demonstrating
splice()/splice() is slow enough we have to optimize it and add kernel
bloat...