From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] Add useful per-connection TCP stats for diagnosis
 purpose.
Date: Fri, 18 Mar 2011 07:05:24 +0100
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Cc: Stephen Hemminger <shemminger@vyatta.com>, netdev@vger.kernel.org
To: Jerry Chu <hkchu@google.com>
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Le jeudi 17 mars 2011 =C3=A0 21:33 -0700, Jerry Chu a =C3=A9crit :

> Yes I'm familiar with ss and how inet_csk_diag_fill() calls into
> tcp_diag_get_info(),..., etc. Like I mentioned previously the netlink
> interface
> requires a new version of reader app (e.g., ss) to ship every time a =
new
> counter is added and exported by the kernel, whereas /proc/net/tcp do=
es
> not have such a problem.
>=20
> Anyway I can add a INET_DIAG_INFO_EXT of some sort to netlink in
> addition to /proc/net/tcp. That's easy to do.
>=20

I suggest adding a getsockopt() or something to gather stats for one
socket. On a loaded machine, /proc/net/tcp is damn slow.

We have TCP_INFO, we could add TCP_INFO_EXT, but taking care of choosin=
g
an interface allowing for extension of the structure.